Lesson Plan Kedua Belas

LESSON PLAN

School : Junior High School
Subject : Mathematics
Grade : VII
Semester : 2 ( Even )
Time Allocation : 2 x 40 Minutes
Meeting : 3

I. Standard of competence : Geometry
5. Reasoning of the relationship between line
with line, line with angle, angle with angle,
and it size.

II. Basic competency : 5.1 Determining relation between two line, size,
and kind of angle.

III. Topic : Line and angle

IV. Indicators : 1. Introducing angles units (degree, minutes,
second, radian).
2. Solve the addition and subtraction with
angles units.

V. Learning out comes : Students be able to solve the addition and
subtraction with angles units.

VI. Appliance and source learning : 1. Matematika SMP Bilingual Grade VII
by Yrama Widya
2. Matematika untuk SMP Kelas VII by
Erlangga

VII. Strategy of learning : Direct instruction

VIII. Scenario of learning activity

A. Introduction

A.1 Opening

1.Informs the indicators of learning , such as today we’ll learn about Introducing angles units (degree, minutes, second, radian) and solve the addition and subtraction with angles units.

2. Gives apperception, such as asks to students
a. What’s the unit which we use to know angles size?
b. What’s the unit which we use to know how long a time?

B. Main Activity

B.1 Explaining

1. Explains relationship between degrees, minutes, seconds, and radian

2 .The students answer the questions in the whiteboard

3. Explains how to solve the addition and subtraction with angles units.

4. The students do the exercise make a teacher in exercise book

5. The students correct their answer. Some representative students write their answer in the whiteboard. The teacher guides which is the right answer

C. Closing

1. The teacher guides students to make conclusion about this topics.
Such as, 1 = 60’
1’ = 60’’

2. Giving homework problems make the teacher

3. The teacher gives task to learn at home about study the next material

IX. Evaluation

1. Evaluation process : Affective, knowledge, and psychomotoric

2. Evaluation product : Exercise (enclosed with key)

Palembang,
Mathematics Teacher

Exercise

1. Express 12 24’9’’
a. in degrees only
b. in minutes only
c. in seconds only
2. Find each sum
a. 2 45’ + 4 28’
b. 3 54’ + 9 48’
c. 20 12’27’’ + 21 20’30’’
d. 13 15’17’’ + 20 50’30’’
e. 18 15’35’’ + 2 20’47’’
f. 10 47’38’’ + 12 40’49’’
3. Find each difference
a. 41 32’57’’ – 21 20’30’’
b. 34 5’47’’ – 13 15’17’’
c. 9 – 5 29’20’’
d. 8 3’’ – 7 28’

Lesson Plan Kesebelas

LESSON PLAN

School : Junior high school
Subject : Mathematics
Grade : VIII
Semester : 2 ( Even )
Time Allocation : 2 x 40 Minutes
Meeting :

I. Standard of competence : Geometry and Measurement
5. Determining part of circle and it size
II. Basic competency : 5.5 Drawing the inner circle and outer circle
of triangle
III. Topic : Circle

IV. Indicators : 1. Determining the length of radius the inner
circle of triangle
2. Determining the length of radius the outer
circle of triangle

V. Learning out comes : Students be able determining the length of radius the inner circle and outer circle of triangle

VI. Appliance and source learning : 1. Student book
2. Charta
3 Student work sheet
4 Matematika SLTP Bilingual 2A by Yrama Widya

VII. Strategy of learning : Inquiry learning , Discussion

VIII. Scenario of learning activity

A. Introduction

A.1 Opening

1.Teacher remind the students about the last topic b asking some question , such as :
a. Teacher draws an triangle ABC
b. One student draw bisector at center A, one student draws bisector at center B, one student draws bisector at center C, one student draws the inner circle of triangle ABC of the center at the point where the three bisector meet
c. Teacher guides if the student has difficulties and teacher guides the right steps
d. Teacher draws a triangle PQR
e. One student draws axis line at center P , one student draws axis line at center Q, one student draws axis at center R, one student draws the outer circle of triangle PQR of the center at the point where the three axis line meet

2.Inform the indicators of learning. Such as today we’ll learning about determining the length of radius the inner circle and the outer circle about triangle
B. Main Activity
B.1 Explaining

1. Teacher shows the length of radius the inner circle and the outer circle of triangle
2. Students do student work sheet in pair
3. Some students presentation their result . Teacher guides the right answer
4. Teacher gives one example how to find the length of radius the inner circle of triangle
5. Teacher give one example how to find the length of radius the outer circle of triangle
6. Students do exercise in their exercise book
7. Students with the teacher correct the exercise. Some representative students write their answer in the white board . Teacher guides the right answer

C. Closing

1. The teacher guides the students to make conclusion about this topics.

Formula of the length of radius the inner circle of triangle =
Formula of the length of radius the outer circle of triangle =
2.Giving homework make the teacher

3. The teacher tell about the activity in the next meeting

IX. Evaluation

1.Evaluation process : Affective, knowledge , and psychomotoric
2. Evaluation product : Exercise and home work ( enclosed with key )

Palembang,
Mathematics Teacher

Lesson Plan Kesepuluh

LESSON PLAN

School : Junior High School
Subject : Mathematics
Grade : VIII
Semester : 2 ( Even )
Time Allocation : 2 x 40 Minutes
Meeting : 4th

I. Standard of competence : Geometry
4. Determining element , part, and size of
the circle
II. Basic competency : 4.4 Calculate the length of the common
tangent line of two circle
III. Topic : circle

IV. Indicators : 1. Draw the tangent line passing through
a point of circle
2. Draw the tangent line passing trough
a point exterior of a circle
3. Calculate the length of the tangent line
to a circle

V. Learning out comes : Students be able draw the tangent line
passing trough a point of a circle and
trough a point exterior of a circle

VI. Appliance and source learning : 1. Student book
2. Charta
3 Student work sheet
4 Matematika SMP Bilingual 2 B by Yrama Widya

VII. Strategy of learning : Direct instruction, Discussion

VIII. Scenario of learning activity

A. Introduction

A.1 Opening

1.Inform the indicators of learning , such as today we’ll learn to draw the tangent line and calculate the length of the tangent lines to a circle

2.Give apperception , such as draw a circle and ask to students where is the point of a circle and the point exterior of a circle

B. Main Activity

B.1 Explaining

1. Using charta explain the steps to draw the tangent line passing trough a point of a circle
2. The students draw the tangent line passing trough a point of a circle in their students work sheet . The teacher guides if they have difficulties .
Some students presentation their result
3. Using charta explain the steps to draw the tangent line passing trough a point exterior of a circle
4. the students draw the tangent line passing trough a point exterior of a circle the teacher guides they have difficulties . Some students presentation their result
5. Explain the value ad formula the tangent line
6. Some student answer some question about calculate of the length of tangent line ( enclosed ) in the white board
7. The students do the exercise make the teacher
8. The students correct their answer . Some representative students write their answer in the with board

C. Closing

1. The teacher guides the students to make conclusion about this topics.
B

A C

2.Giving homework from students book

3. The teacher gives task to learn at home about study the next material
Evaluation
1.Evaluation process : Affective, knowledge , and psychomotoric
2. Evaluatin product : Exercise and home work

Palembang,
Mathematics Teacher

Lesson Plan Kesembilan

LESSON PLAN

School : Junior High School
Subject : Mathematics
Grade : VII
Semester : 2 ( Even )
Time Allocation : 2 x 40 Minutes
Meeting : 7th

I. Standard of competence : Geometry
5. Determining connection between line with
line , line with angle , angle with angle , and
it size
II. Basic competency : 5.1 Determining connection between two line, i
It size , and kind of angles.

III. Topic : Line and angles

IV. Indicators : 1. Using the properties of angle based their
located and their sum to solve the problem

V. Learning out comes : Students be able to solve the problem using the
properties of angles based their located and
their sum

VI. Appliance and source learning : 1. Student book
2. Matematika Class VII by Erlangga
3. Matematika Class VII by Regina
4. Chart , compass, protractor

VII. Strategy of learning : Direct instruction, answer – question

VIII. Scenario of learning activity

A. Introduction

A.1 Opening

1.Inform the indicators of learning , such as today we’ll learn about angles properties based their located and their sum .

2.Review the topic about measure an angle in clock

3.Give motivation, such as learn about angles are important to application in daily life.

B. Main Activity

B.1 Explaining

1. Explain about the properties of angle beside their located and their sum
a. The relationship two angles if the angles are supplementary
b. The relationship two angles if the angles if the angles are complementary
c. The relationship two angles if the angles if the angles are vertical students

2. Some students answer the question about relation of two angle

3. Students do exercise in their exercise book

4. Students with teacher correct in their answer in exercise
some student write their answer in the white board
the teacher guides the right answer

C. Closing

1. The teacher guides students to make conclusion about this topics
There are steps to measure an angle :
– The size of supplementary angles are 180
– The size complementary angles are 90

– The size of vertical angles are equals

2. The teacher tell about the activity in the next meeting

IX. Evaluation

1. Evaluation process : Affective, knowledge, and psychomotoric

2. Evaluation product : Exercise

Palembang,
Mathematics Teacher

Lesson Plan Kedelapan

LESSON PLAN

School : Junior High School
Subject : Mathematics
Grade : VII
Semester : 2 ( Even )
Time Allocation : 2 x 40 Minutes
Meeting : 7th

I. Standard of competence : Geometry
5. Determining connection between line
with line, line with the angle , and it size
II. Basic competency : 5.1 Determining connection two line
it size , and kind of the angles
III. Topic : line and angle

IV. Indicators : Using the properties of angles based their located and their sum to solve
the problem

V. Learning out comes : Students be able to solve the problem using the properties of angles based
Their located and their sum
VI. Appliance and source learning : 1. Student book
2. Matematika SMP Class VII by Regina
3 Chart, Compass , protractor

VII. Strategy of learning : Direct instruction, Answer – question
VIII. Scenario of learning activity

A. Introduction

A.1 Opening

1.Inform the indicators of learning , such as today we’ll learn about properties of angles based their located and their sum

2.Review the topic about measure an angle in clock

B. Main Activity

B.1 Explaining
1. Explain about the properties of angles based their located and their sum
a. The relationship two angles if the angles are supplementary
b. The relationship of two angles if the angles are complementary
c. The relationship of two angles if the angles are vertical

2. Some students answer the question about the relationship of two angles , such as :
a. 88 and 92 are called …
b. The supplementary angle of 25 is…

c.

130 X

3. Students do exercise in their exercise book
4. Students with teacher correct the answer.
Some students write their answer in the white board
The teacher guides the right answer

C. Closing

1. The teacher guides the students to make conclusion about this topic.
The size of supplementary angles are 180
The size of complementary angles 90
The teacher guides the right answer

IX. Evaluation

1.Evaluation process : Affective, knowledge , and psychomotoric
2. Evaluation product : Exercise

Palembang,
Mathematics Teacher

Exercise

1. If < A = 42 then the size of < B if < A and < B are :
a. Complementary b. Supplementary c. Vertical

2. Find the size of X, Y, Z !

a. b. c.

X 65
50 y 53
y z

Exercise

1. If < A = 42 then the size of < B if < A and < B are :
a. Complementary b. Supplementary c. Vertical

2. Find the size of X, Y, Z !

a. b. c.

X 65
50 y 53
y z

Exercise

1. If < A = 42 then the size of < B if < A and < B are :
a. Complementary b. Supplementary c. Vertical

2. Find the size of X, Y, Z !

a. b. c.

X 65
50 y 53
y z

Homework

1. Find the size of angles in each figure :
a. b. c.

2. The angles A dan B are supplementary angles of ratio 4 : 5 . The size of angles B is…
3.The size of angle A = of a right angles , so that the size of angle A =…
4. Given the angle equals 15 less than twice their supplementary .
If the supplementary angle is y , find the size of y !

Homework

1. Find the size of angles in each figure :
a. b. c.

2. The angles A dan B are supplementary angles of ratio 4 : 5 . The size of angles B is…
3.The size of angle A = of a right angles , so that the size of angle A =…
4. Given the angle equals 15 less than twice their supplementary .
If the supplementary angle is y , find the size of y !

Lesson Plan Ketujuh

LESSON PLAN

School : Junior High School
Subject : Mathematics
Grade : VII
Semester : 2 ( Even )
Time Allocation : 2 x 40 Minutes
Meeting : 5th

I. Standard of competence : Geometry
5. Determining connection between line
with line, line with the angle , and it size
II. Basic competency : 5.1 Determining connection two line
it size , and kind of the angles
III. Topic : line and angle

IV. Indicators : 1. Explain kind of difference angles ( acute
angle, right angle, obtuse angle, straight
angle, reflex angle )
2. Determine to solve contextual problem
using angle size

V. Learning out comes : Students be able to explain kind of the difference angles and to solve contextual problem using angle size

VI. Appliance and source learning : 1. Student book
2. Matematika SMP Class VII by Regina
3 Compass

VII. Strategy of learning : Direct instruction, Discussion

VIII. Scenario of learning activity

A. Introduction

A.1 Opening

1.Inform the indicators of learning , such as today we’ll learn about kind of angles

2.Give apperception , such as measure an angle and give some question to student about angle
B. Main Activity

B.1 Explaining

1. Some students draw angle and their partner measure the size of that angle
2. Teacher explain about kind of the angle
3. Student with her / his partner tell about What is the size of their angle and explain about What the angle which they made, the teacher guides the right answer
4. Teacher explain contextual problem using clock
5. Some student answer some question about calculate of the length of tangent line ( enclosed ) in the white board
6. Students do exercise in their exercise book
7. Some representative students write their answer in the white board . The teacher guides the right answer

C. Closing

1. The teacher guides the students to make conclusion about this topics.
Kind of the angles are acute angle , right angle , obtuse angle , straight angle , reflex angle

2.Giving homework make the teacher

3. The teacher tell about the activity in the next meeting

IX. Evaluation

1.Evaluation process : Affective, knowledge , and psychomotoric
2. Evaluation product : Exercise and home work

Palembang,
Mathematics Teacher

Lesson Plan Keenam

LESSON PLAN

School : Junior High School
Subject : Mathematics
Grade : VII
Semester : 2 ( Even )
Time Allocation : 2 x 40 Minutes
Meeting : 4th

I. Standard of competence : Geometry
5. Reasoning of the relationship between line
with line, line with angle, angle with angle,
and it size.

II. Basic competency : 5.1 Determining relation between two line, size,
and kind of angle.

III. Topic : Line and angle

IV. Indicators : 1. Measuring an angle
2. Drawing an angle

V. Learning out comes : Students be able to measure an angle using
protractor and draw an angle

VI. Appliance and source learning : 1. Student book grade VII
2. Matematika Class VII by Regina
3. Work sheet
4. Ruler , pencil , protractor

VII. Strategy of learning : Direct instruction, discussion

VIII. Scenario of learning activity

A. Introduction

A.1 Opening

1.Inform the indicators of learning , such as today we’ll learn about measuring an angle using protractor and drawing an angle

2.Give apperception, such as tell the students that in daily life we always meet angle.

3.Give motivation, such as learn about angles are important to application in daily life.

B. Main Activity

B.1 Explaining

1. Explain about angle
a. Teacher draws an angle
b. Tell meaning of an angle and the example daily life
c. Give the name an angle and mention their elements
d. As a feet back , teacher gives an angle and asks the students what the name of the angle and mention the elements

2 .Give example how to measure an angle with protractor

3. Give example how to draw an angle

4. The students do work sheet in pair . The teacher guides if there are students have difficulties
5. The students presentation their discuss . The teacher guides the right answer

6.The students do the exercise make a teacher in exercise book

7. The students correct their answer . Some representative students write their answer in the white board . The teacher guides which is the right answer .

C. Closing

1. The teacher guides students to make conclusion about this topics
There are steps to measure an angle :
a. Put the protractor in one of the arm of angle when the 0 meet the arm angle
b. The center of protractor meet the vertex

c. Consider the number in protractor whose show by the other arm angle

2. Giving homework make the teacher

3. The teacher gives task to learn at home about study the next material. Next material is about kind of angle

IX. Evaluation

1. Evaluation process : Affective, knowledge, and psychomotoric

2. Evaluation product : Exercise and home work ( Enclosed with key )

Palembang,
Mathematics Teacher

Lesson Plan Kelima

LESSON PLAN

School : Junior High School
Subject : Mathematics
Grade : VII
Semester : 2 ( Even)
Time Allocation : 2 x 40 Minutes
Meeting : 2

I. Standard of Competency : Geometry
5. Determining relationship line with line, line with
angle, angle with angle, and determining it size.
II. Basic Competence : 5.2 Reasoning properties of angle formed if two lines
intersecting or two parallel lines intersecting with
other line.
III. Topic : Lines and angles.
IV. Indicators : Using concept properties of angle formed if two lines
intersecting or two parallel lines intersecting with other
line to solve the problem.
V. Learning out comes : Students be able to solve the problem using concept
properties of angle formed if two lines intersecting or
two parallel lines intersecting with other line to solve
the problem.
VI. Appliance and source learning: 1. Student book
2. Student book make the teacher
3. Multimedia
4. Pencil, ruler, educational appliances
VII. Strategy of learning : Approach PMRI
VIII. Scenario of learning activity
A. Introduction
A.I Opening
1. Using multimedia inform the indicators and strategy of learning
2. Give apperception, such as :
a. Using multimedia perform some contextual figure and ask to students what are that figure, where are you meet that figure
b. Tells to students about what must they doing in this topic

B. Main Activity
B.1 Explaining
1. Students together based on their groups which have been before.
2. Students do activity based instruction which inform by teacher
3. Students answer questions in student book make the teacher.
To answer the questions, they must discuss with their friend in groups.
The teacher guides if there are students have difficulties.
4. Some groups presentation of their answer.
The other groups discuss the answer together.
5. Using multimedia teacher guides the right answer and guides the students to make
conclusion about their discussion.
6. The students do the exercise make the teacher.
7. The students correct their answer.
Some representative students write their answer in the whiteboard.
The teacher guides which is the right answer.

C. Closing
1. Teacher guides the students to make conclusion about this topic.
The manner to solve the problem about properties of angles and lines are :
a. Using concept properties of angle formed if two lines intersecting or two parallel lines
intersecting with other line
b. Draw one or more parallel lines and then using concept properties of angle formed if two lines intersecting or two parallel lines intersecting with other line

2. Giving homework make the teacher.
3. The teacher tells about the next activity in the next meeting.

IX. Evaluation
1. Evaluation process: Affective, knowledge, psychomotoric
2. Evaluation product : Exercise and homework (enclosed with key)

Palembang,
Mathematics Teacher

LESSON PLAN

School : Junior High School
Subject : Mathematics
Grade : VII
Semester : 2 ( Even)
Time Allocation : 2 x 40 Minutes
Meeting : 1
I. Standard of Competency : Geometry
5. Determining relationship line with line, line with
angle, angle with angle, and determining it size.
II. Basic Competence : 5.2 Reasoning properties of angle formed if two lines
intersecting or two parallel lines intersecting with
other line.
III. Topic : Lines and angles.
IV. Indicators : 1. Identifying angle formed if two lines intersecting or
two parallel lines intersecting with other line
2. Determining the value of corresponding angles,
alternate interior angles, alternate exterior angles,
corresponding interior angles, corresponding
exterior angles.
V. Learning out comes : Students be able to identify angle formed if two lines
intersecting or two parallel lines intersecting with
other line and determining it size.
VI. Appliance and source learning: 1. Student book
2. Student book make the teacher
3. Multimedia
4. Pencil, ruler, protractor, rope, chopstick
VII. Strategy of learning : Approach PMRI
VIII. Scenario of learning activity
A. Introduction
A.I Opening
1. Using multimedia inform the indicators and strategy of learning
2. Give apperception, such as :
a. Giving one paper to each students , students answer the question in that paper
b. Using multimedia teacher performs the questions in that paper.
Teacher and students correct the question together.
Some representative students answer the questions orally.
Teacher guides the right answer.
B. Main Activity
B.1 Explaining
1. Students sit based on their groups which have been before.
2. Students do activity based instruction which inform by teacher
3. Students answer questions in student book make the teacher.
To answer the questions, they must discuss with their friend in groups.
The teacher guides if there are students have difficulties.
4. Some groups presentation of their answer.
The other groups discuss the answer together.
5. Using multimedia teacher guides the right answer and guides the students to make
conclusion about their discussion.
6. The students do the exercise make the teacher.
7. The students correct their answer.
Some representative students write their answer in the whiteboard.
The teacher guides which is the right answer.

C. Closing
1. Teacher guides the students to make conclusion about this topic.
a. The size of corresponding angles are equals.
b. The size of alternate interior angles are equals
a. The size of alternate exterior angles are equals
b. The sum of corresponding interior angles are 180
c. The sum of corresponding exterior angles are 180
2. Giving homework make the teacher.
3. The teacher tells about the next activity in the next meeting.

IX. Evaluation
1. Evaluation process : Affective, knowledge, psychomotoric
2. Evaluation product : Exercise and homework (enclosed with key)

Palembang,
Mathematics Teacher

Lesson Plan Keempat

LESSON PLAN

School : Junior High School
Subject : Mathematics
Grade : VIII
Semester : 2 ( even )
Time Allocation : 2 x 40 minutes
Meeting : 1St

I. Standard of Competence : Geometry and Measurement
4. Determine element , part , and size of the
circle

II. Basic competency : 4.2 Determine the area of circle

III. Topic : Circle

IV. Indicators : Find out formula the area of a circle by
using an experiment

V. Learning out comes : Students be able determine formula the
area of circle

VI. Appliance and source learning : 1. Multimedia
2. Students work sheet
3. Scissor and glue

VII. Strategy of learning : Inquiry learning , discussion

VIII. Scenario of learning activity

A.Introduction

A.1 Opening

1.Inform the indicators of learning , such as today well learn about find out formula the area of a circle by using on experiment

2. Give apperception, such as using a clock ask to students which are the radius , diameter, and sector

B.Main Activity

B.1 Explaining

1.The students sit based their group

2.The teacher delivers students work sheet to each group and explain how to do the work sheet

3.The students discuss to find out formula the area of a circle by using can experiment

4.The teacher guides the students if they have difficulties

5. Some students presentation of their discuss of the topic

6.The students do the exercise

7.The students correct their answer.
Some representative students write their answer in the whiteboard.
The teacher guides which is the right answer

C. Closing

1.Teacher guides the students to make conclusion about this topics
Formula the area of a circle is A =

2. Giving homework page 207 task 6.2 no.2

3. The teacher gives task to learn at home about study the next material

IX. Evaluation

1.Evaluation process : Affective, knowledge, and psychomotoric

2.Evaluation product : Exercise (enclosed with key)

Palembang,
Mathematics Teacher

Students work sheet
Date :
Group :
Members : 1.
2.
3.
4.
Topics : Circles
Indicators : Find out formula the area of a circle by using an experiment

Instructions :
1. Do it in groups
2. With scissors , cut each part of half a circle based the sectors
3. Arrange those parts in paper the figure like this

4. Arrange those parts so that the shape found forms like a…….
5. What is the formula of the area rectangle ?
6. Which are the length and the width ?

Width = ….

Length = …..

7. Is the area of rectangle same with the area of circle ?
8. So, area of circle = Area of rectangle in this experiment
= ….. X ….
= ….. X ….
= ….. X ….
= …..
9. Conclusion ,
Based this experiment ,
What’s formula the area of a circle ?

10. If r = d , the area of a circle = …..
= …..
= ….
= ….

Key Students worksheet

No Steps Score
4

5

6

7

8

9

10 Rectangle

A = l x w

Length = ½ C
Width = r

yes, it is

So, area of circle = Area of rectangle in this experiment
= l X w
= ½ C X r
= ½ 2 r X r
=

A =

If r = d , the area of a circle =
=
=
=
1

1

2
2

2

2
2
2
1

1

1

1

1

1

Total 20

Exercise

1. The length of radius of circle is 7 cm
Find the area of the circle : a) Using  =
b) Using  = 3,14

2. The length of diameter of circle is 35 cm .
Find the area of the circle ! (  = )
3. The area of a circle is 5544 cm (
Find a ) The length of radius of circle
b ) The length of diameter of circle

KEYS

No Steps Score
1

2

3 a) A = r
= X 7 X 7
= 154 cm
b) A = r
= 3,14 X 7 X 7
= 153, 86 cm

A = X d
= X X 35 X 35
= 962,5 cm

a) r =

=

= 1764

r =
= 42 cm

b) d = 2r
= 2 X 24
= 84 cm

1
1

1

1
1
1

2

1

1

3

1

1

1
1

1
1
1
Total 20

Lesson Plan Ketiga

LESSON PLAN

School : Junior High School
Subject : Mathematics
Grade : VII
Semester : 2 ( Even )
Time Allocation : 2 x 40 Minutes
Meeting : 1

I. Standard of competence : Algebraic
4. Using concept set and Venn diagram
In problem solving

II. Basic competency : 4.5 Using concept sets in problem
solving

III. Topic : Sets

IV. Indicators : Determining to solve the problems

V. Learning out comes : Students be able determine to solve the
problems by using concept sets in
problem solving

VI. Appliance and source learning : 1. Multimedia
2. Matematika SMP Bilingual Grade VII
by Yrama Widya

VII. Strategy of learning : Direct instruction , discussion

VIII. Scenario of learning activity

A. Introduction

A.1 Opening

1.By using multimedia to inform the indicators of learning , such as today we’ll learn about using concept sets in problem solving .
If the students have finished this learning , the students be able determine to solve the problem solving (5’)

2. By using multimedia to give apperception, such as performance question and ask to students how to the solution in this case. After that, remind about intersection set and union set

B. Main Activity

B.1 Explaining

1. By using multimedia to give one example about problem solving in the real life and explain how to do it

2 .The students do the worksheet in pair, the teacher guides if there are students have difficulties

3. Some students presentation of their discuss of the topic

4. The students do the exercise in exercise book

5. The students correct their answer. Some representative students write their answer in the whiteboard. The teacher guides which is the right answer

C.Closing

1. The teacher guides students to make conclusion about this topics.
To solve the problems can do it by Venn diagram
To solve the problems can do it by formula : n(U) = n(A) + n(B) – n(AB) + n(AB)’

2. Giving homework problems make the teacher

3. The teacher gives task to learn at home about study the next material

IX. Evaluation

1. Evaluation process : Affective, knowledge, and psychomotoric

2. Evaluation product : Exercise (enclosed with key)

Palembang,
Teacher,

Date :
Group :
Members : 1.
2.
Topics : Sets
Indicators : Determining to solve the problems

1. In this class, there are 24 students, 10 students who like mathematics, 6 students who like English, and 5 students who like both of them. Find the number of students who don’t like either mathematics or English ?
Known :
Suppose : M = the set of students who like mathematics
E = the set of students who like English
n(U) = 24
n(M) = 10
n(E) = ….
n(M∩E) = 5
Unknown : n(MỤE)’ =…?
Solution : M is the set of students who like mathematics
E is the set of students who like English

M E

n(U) = n(M) + n(E) – n(M∩E) + n(MỤE)’
24 = 10 + … – 5 + n(MỤE)’
24 = … + n(MỤE)’
n(MỤE)’ = 24 – …
n(MỤE)’ = …

so, the number of students who don’t like either mathematics or English is …

2. In this class, there are 24 students, where 16 students who like eat fried chicken, 3 students like both fried chicken and meat ball, and 4 students don’t like either fried chicken or meat ball. Find the number of children who like eat meat ball ?

Known :
Suppose:F = the set ofstudents who like eat fried chicken
M = the set of students who like eat meat ball
n(U) =…
n(F) = 16
n(F∩M) = 3
n(FỤM)’ = …
Unknown : n(M) = …?
Solution: F is the set of students who like fried chicken
M is the set of students who like meat ball

F
M

n(U) = n(F) + n(M) – n(F∩M) + n(FỤM)’
… = 16 + n(M) – 3 + …
… = … + n(M)
n(M) = … – …
n(M) = …

so, the number of children who like eat meat ball is …

No Steps Score
1

Known :
Suppose :
M = the set of students who like mathematics
E = the set of students who like English
n(U) = 24
n(M) = 10
n(E) = 6
n(M∩E) = 5
Unknown : n(MỤE)’ =…?
Solution :
M is the set of students who like mathematics
E is the set of students who like English

M E

1
13

n(U) = n(M) + n(E) – n(M∩E) + n(MỤE)’
24 = 10 + 6 – 5 + n(MỤE)’
24 = 11 + n(MỤE)’
n(MỤE)’ = 24 – 11
n(MỤE)’ = 13

so, the number of students who don’t like either mathematics or English is 13 students

1
1
1
1
1

2

1
1

1
2
Known :
Suppose:
F= the set of students who like eat fried chicken
M = the set of students who like eat meat bal
n(U) = 24
n(F) = 16
n(F∩M) = 3
n(FỤM)’ = 4
Unknown : n(M) = …?
Solution:
F is the set of students who like fried chicken
M is the set of students who like meat ball

1
1
1
1
1

F
M 4

4

n(U) = n(F) + n(M) – n(F∩M) + n(FỤM)’
24 = 16 + n(M) – 3 + 4
24 = 17 + n(M)
n(M) = 24 – 17
n(M) = 7

so, the number of children who like eat meat ball is 7 students

2

1
1

1

Total 20

EXERCISE

1. There are 40 students in a class , where 25 students who wear rings, 20 students who wear earrings, and 11 students who wear both rings and earrings. Find the number of students who wear neither rings nor earrings ?

2. There are 70 children in a hostel. Among these children, 35 children can speak English, 8 children can speak both English and Chinese, and 11 children can’t speak either English or Chinese. Find the number of children can speak Chinese ?

3. Of a number of children given that 25 children who like play piano . 21 children who like play guitar and 9 children who like both of them . The number of children in that group is….

4. Of a group of 46 students , 33 students who like green color , 27 students who like yellow color and 12 students who don’t like either green or yellow . The number of students who like both green and yellow is….

Keys
No Steps Score
1 Known :
Suppose : R = the set of students who wear rings
E = the set of students who wear earrings
n(U) = 40
n(R) = 25
n(E) = 20
n(R∩E) = 11
Unknown : n(RỤE)’=…?
Solution :
n(U) = n(R) + n(E) – n(R∩E) + n(RỤE)’
40 = 25 + 20 – 11 + n(RỤE)’
40 = 34 – n(RỤE)’
n(RỤE)’ = 40 – 34
n(RỤE)’ = 6

so, the number of students who wear neither rings nor earrings is 6 students

1
1
1
1
1

1
1

1
2 Known :
Suppose : E = the set of children can speak English
C = the set of children can speak Chinese
n(U) = 70
n(E) = 35
n(EỤC)’ = 11
n(E∩C) = 8
Unknown : n(E) =…?
Solution :
n(U) = n(E) + n(C) – n(E∩C) + n(EỤC)’
70 = 35 + n(C) – 8 + 11
70 = 38 – n(C)
n(C) = 70 – 38
n(C) = 32

so, the number of children can speak Chinese is 32 children

1
1
1
1
1

1
1

1
3 Known :
Suppose : P = the set of children who like play piano
G = the set of children who like play guitar
n(P) = 25
n(G) = 21
n(P∩G) = 9
Unknown : n(U)=…?
Solution :
n(U) = n(P) + n(G) – n(P∩G)
n(U) = 25 + 21 – 9
n(U) = 37

so, the number of children in that group is 37 children

1
1
1
1

1
1
1

4 Known :
Suppose : G = the set of students who like green color
Y = the set of students who like yellow color
n(U) = 46
n(G) = 33
n(Y) = 27
n(GỤY)’ = 12
Unknown : n(G∩Y) =…?
Solution :
n(U) = n(G) + n(Y) – n(G∩Y) + n(GỤY)’
46 = 33 + 27 – n(G∩Y) + 12
46 = 72 – n(G∩Y)
n(G∩Y) = 72 – 46
n(G∩Y) = 26

so, the number of students who like both green and yellow is 26 students

1
1
1
1
1

1
1

1
Total 31