Detailed Lesson Plan in Associative Property of Addition

 

Detailed Lesson Plan in Mathematics 2 I. 

Objectives

At the end of the lesson, the pupils should be able to:  

Discuss the meaning of Associative Property of Addition

 

Show that changing the groupings of the addends does not affect the sum

II. 

Subject Matter Topic: Associative Property of Addition Reference: Basic Mathematics for Elementary Level, pages 52-53 52 -53 Materials: Number Cards, Pictures, Pen, Paper

III. 

Procedure Teacher’s Activity  Activity  A.  Preliminary Activities Greetings Good afternoon class. Checking of Attendance Is there any absent for today? Review What was our topic last meeting?

Very Good! What is Commutative Property of Addition?

Pupils’ Activity  Activity 

Good afternoon Sir.

There is no absent for today.

It is about Commutative Property of Addition.

Commutative Property of Addition states that changing the order of the addends does not change the sum.

Very well said! Give him “Yes Clap”!   Clap”! Vocabulary Again, let us review what are Addends?

What is Sum?

I have here some exercises and kindly give the sum. a.  7 + 9 =  b.  9 + 7 =

Yes!

Addends are numbers used in an addition problem Sum is the result or the total of adding two or more numbers.

7 + 9 = 16 9 + 7 = 16

 

c.  10 + 2 = d.  2 + 10 =

10 + 2 = 12 2 + 10 = 12

B.  Developmental Activities Motivation I have here a Box of Numbers. Inside the box are number cards

from one (1) to ten (10). Each group will need to pick three (3) number cards that the sum of these three cards is equal to the number that I will be giving.

[1,2,3,4,5,6,7,8,9,10]

The sum of three numbers is 17. The sum of three numbers is 18. The sum of four numbers is 20.

3, 6 and 8 1, 7 and 10 2, 4, 5 and 9

Give the Yes clap.

Yes!

Presentation of the Lesson Let’s say that I have 3 numbers: 3, 6 and 8, we are going to put a  parenthesis on the first and second addends. Outside of this, we will write the third addend.

 Now, we will change the  position of the parenthesis by  putting it in the second and third addends.

(3+6)+8 9 + 8 = 17

3+(6+8) 3 + 14 = 17

 Now what if I will put 3 and 8 inside the parenthesis first then add 6 outside. Do you think that we will get the same answer? I have 3 numbers: 1, 7 and 10, we are going to put a parenthesis on the first and second addends. Outside of this, we will write the third addend.  Now, we will change the  position of the parenthesis by

(3+8)+6 11 + 6 = 17 Yes Sir! We will get the same answer.

( 1 + 7 ) + 10 8 + 10 = 18

 

 putting it in the second and third addends. 1 + ( 7 + 10) 1 + 17 = 18  Now what if I will put 1 and 10 inside the parenthesis first then add 7 outside. Do you think that we will get the same answer?

Let’s say that I have have 4 numbers: 2, 4, 5 and 9, we are going to put a parenthesis on number 2 and 4. Outside of this, we will write the 5 and 9.  Now, we will change the  position of the parenthesis by  putting it in the second and third addends.  Now, we will change the  position of the parenthesis by  putting it in the third and fourth addends.

( 1 + 10 ) + 7 11 + 7 = 18 Yes, we will get the same answer.

(2+4)+5+9 6 + 5 + 9 = 20

2+(4+5)+9 2 + 9 + 9 = 20

2+4(5+9) 2 + 4 + 14 = 20

 Now what if I will put the  parenthesis on the first and second addends and the put again another parenthesis to the third and fourth addends. Do you think that we will get the same answer?

Fixing Skills Group the addends and find the sum. a.  9 + 3 + 15 =

(2+4)+(5 +9) 6 + 14 = 20 Yes, we will get the same answer.

( 9 + 3 ) + 15 = 12 + 15 = 27 9 + ( 3 + 15) = 9 + 18 = 27

 

 b.  16 + 5 + 2 =

( 16 + 5 ) + 2 = 21 + 2 = 23 16 + ( 5 + 2 ) = 16 + 7 = 23

c.  8 + 11 +14 =

( 8 + 11 ) +14 = 19 + 14 = 33 8 + ( 11 + 14) = 8 + 25 = 33

d.  7 + 10 + 4 =

( 7 + 10 ) + 4 = 17 + 4 = 21 7 + ( 10 + 4 ) = 7 + 14 = 21

e.  5 + 9 + 15

( 5 + 9 ) + 15 = 14 + 15 = 29 5 + ( 9 + 15 ) = 5 + 24 = 29

Application  We will divide the class into 2 groups. Each group will receive a folder containing 8 cards. Each group will need to find the correct pair of cards. There are 4  pairs or correct answers.

Group 1 20+13 = 9+24

7+9 = 2+14

(2+5)+9 =

7+9 = 2+14

33 = 33

16 = 16

2+(5+9)

16 = 16

(8+13)+21 =

(9+11)+13 =

(8+13)+21 =

21+21 = 8+34

8+(13+21)

9+(11+13)

8+(13+21)

42 = 42

21+21 = 8+34 42 = 42

19+6 = 11+14

(9+11)+13 =

20+13 = 9+24

25 = 25

9+(11+13)

33 = 33

(2+5)+9 =

(11+8)+6 =

(11+8)+6 =

2+(5+9)

11+(8+6)

11+(8+6)

19+6 = 11+14 25 = 25

 

  Group 2 20+13 = 9+24

7+9 = 2+14

(2+5)+9 =

7+9 = 2+14

33 = 33

16 = 16

2+(5+9)

16 = 16

(8+13)+21 =

(9+11)+13 =

(8+13)+21 =

8+(13+21)

9+(11+13)

8+(13+21)

21+21 = 8+34 42 = 42

21+21 = 8+34

19+6 = 11+14

42 = 42

25 = 25

(2+5)+9 =

(11+8)+6 = 11+(8+6)

2+(5+9)

C.  Generalization What is Associative Property of Addition?

Very Good! And how are the numbers grouped together?

(9+11)+13 = 9+(11+13) (11+8)+6 = 11+(8+6)

20+13 = 9+24 33 = 33

19+6 = 11+14 25 = 25

Associative Property of Addition states that changing the groupings of the addends does not change the sum. This states that you can add regardless of how the numbers are grouped. They were grouped together using the  parenthesis. Either we put the  parenthesis on the first and second addends and then copy the third addend and find the sum. Or copy the first addend and put the parenthesis on the second and third addend and find the sum.

IV. 

Evaluation Write the missing numbers. The following items show Associative Property of Addition.

1.  ( 13 + 21 ) + 25 = 13 + ( 21 + 25 )  ________ + 25 = 13 + ________  ______ = ______

 

2.  ( 11 + 16 ) + 21 = 11 + ( 16 + 21 )  ________ + 21 = 11 + ________  ______ = ______ 3.  ( 16 + 17 ) + 18 = 16 + ( 17 + 18 )  ________ + 18 = 16 + ________  ______ = ______ 4.  ( 15 + 18 ) + 20 = 15 + ( 18 + 20 )  ________ + 20 = 15 + ________  ______ = ______ 5.  ( 12 + 19 ) + 26 = 12 + ( 19 + 26 )  ________ + 26 = 12 + ________  ______ = ______ V. 

Homework Group the addends and find the sum. 1.  23 + 27 + 31 = 2.  25 + 19 + 11 = 3.  10 + 15 + 20 = 4.  11 + 23 + 17 = 5.  17 + 22 + 27 =

 

Republic of the Philippines Polytechnic College of Botolan Botolan, Zambales

Detailed Lesson Plan on Mathematics 2

Associative Property of Addition

Submitted by: Alvin M. Buyore BEED 2A

Submitted to: Dr. Isabel F. Asuncion Instructor