Addition of 2 or 3 Digit Numbers using the Partial Sums Method (Primary 3)

MATHEMATICS

FIRST TERM  

WEEK 9

PRIMARY 3

THEME – WHOLE NUMBERS 

PREVIOUS LESSON – 

TOPIC – ADDITION OF WHOLE 2 OR 3 DIGIT NUMBERS – PARTIAL SUMS METHOD 

LEARNING AREA

1. Introductory Activities

2. Addition of 2 Digit Numbers

3. Addition of 3 Digit Numbers

PERFORMANCE OBJECTIVES 

By the end of the lesson, the pupils should have attained the following objectives (cognitive, affective and psychomotor) and should be able to –

add 2 or 3 digit numbers by partial sum method.

ENTRY BEHAVIOUR

Addition of Numbers

 

INSTRUCTIONAL MATERIALS

The teacher will teach the lesson with the aid of:

Charts and flash cards, etc. Addition cards, Fraction card, Fraction board, Counters, charts, Abacus, etc.

METHOD OF TEACHING – Choose a suitable and appropriate methods for the lessons.

Note – Irrespective of choosing methods of teaching, always introduce an activities that will arouse pupil’s interest or lead them to the lessons. 

REFERENCE MATERIALS

1. Scheme of Work

2. 9 – Years Basic Education Curriculum

3. Course Book

4. All Relevant Material

5. Online Information

CONTENT OF THE LESSON  

LESSON ONE – INTRODUCTORY ACTIVITIES 

Teacher’s/Pupil’s Activities – Quick guide and assessment on addition of whole numbers with or without remainder –

Quick Assessment 

1. 3 4 5 + 4 6 6

2. 2 9 3 + 2 3 9

 

Solution 1 – Expanded Method

3 4 5 + 4 6 6

   3¹ 4¹ 5

+ 4  6  6

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    8  1  1

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Therefore, 3 4 5 + 4 6 6 = 8 1 1

 

 

Solution 2 – Expanded Method

2 9 3 + 2 3 9

    2¹ 9¹ 3

+ 2  3  9

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   5  3  2

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Therefore, 2 9 3 + 2 3 9 = 5 3 2

ADDITION OF 2 DIGIT NUMBERS BY PARTIAL SUMS METHOD 

Teacher’s/Pupil’s Activities – Guides the pupils to understand the concept of add 2 digit numbers by partial sums method.

Working Examples 

1. 2 5 + 1 6

2. 3 8 + 2 7

 

Solution 1

2 5 + 1 6

      2 5 = 20 + 5

  + 1 6 = 10 + 6

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            = 30 + 11

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Partial Sums Method 

   3 0

+ 1 1

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 4 1

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Therefore, 2 5 + 1 6 = 4 1

 

Solution 2

3 8 + 2 7

   3 8 = 30 + 8

+ 2 7 = 20 + 7

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          = 50 + 15

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Partial Sums Method 

    5 0

+ 1 5

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 6 5

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Therefore, 3 8 + 2 7 =  6 5

LESSON EVALUATION/ASSIGNMENT

Add the following –

1. 5 9 and 3 4

2. 7 6 and 1 6

3. 7 9 and 4

LESSON TWO – ADDITION OF 3 DIGIT NUMBERS BY PARTIAL SUMS METHOD 

Teacher’s/Pupil’s Activities – Guides the pupils to understand the concept of add 3 digit numbers by partial sums method.

Working Examples

1. 3 4 5 + 4 6 6

2. 2 9 3 + 2 3 9

Solution 1 – Expanded Method

3 4 5 + 4 6 6

   3 4 5 = 300 + 40 + 5

+ 4 6 6 = 400 + 60 + 6

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                   = 700 + 100 + 11

_________________________________

 

Partial Sums Method 

          1 1

       1 0 0

   + 7 0 0

          _________________________________

      8 1 1

_________________________________

 

Therefore, 3 4 5 + 4 6 6 = 8 1 1

Solution 2 – Expanded Method

2 9 3 + 2 3 9

    2 9 3 = 200 + 90 + 3

+ 2 3 9 = 200 + 30 + 9

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                  = 400 + 120 + 12

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Partial Sums Method

       1 2

+ 1 2 0

+ 4 0 0

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   5 3 2

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Therefore, 2 9 3 + 2 3 9 = 5 3 2

 

LESSON EVALUATION/ASSIGNMENT 

1. 5 5 1 + 3 6 9

2. 3 9 5 + 2 0 7

3. 3 6 0 + 1 1 1

LESSON THREE – REVISION AND TEST OF ADDITION OF 2 AND 3 DIGIT NUMBERS BY PARTIAL SUMS METHOD 1

WORKBOOK – WEEKLY ASSESSMENT 

• First Term Workbook – Weekly Assessment for Mathematics (Primary 3)

 

PRESENTATION

To deliver the lesson, the teacher adopts the following steps:

1. To introduce the lesson, the teacher revises the previous lesson. Based on this, he/she asks the pupils some questions;

2. Guides pupils to add 2 or 3 digit numbers by partial sum method.

Pupil’s Activities – Add 2 or 3 digit numbers by partial sum method.

CONCLUSION

• To conclude the lesson for the week, the teacher revises the entire lesson and links it to the following week’s lesson.

• Next Lesson –

LESSON EVALUATION 

Pupils to add 2 or 3 digit numbers by partial sum method.