# Addition of Three Digit Numbers Without Regrouping

**Subject : **

Mathematics

**Term :**

First Term

**Week:**

Week 7

**Class :**

Primary 3/ Basic 3

**Topic** : Addition of Three Digit Numbers Without Regrouping

**Previous lesson : **

The pupils have previous knowledge of comparison and Ordering of Fractions

**Behavioural objectives :**

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

- Add up figures that are written in three digits under Hundreds, Tens and Units
- Arrange the sums of three digit numbers correctly under Hundreds, Tens and Units without making mistakes
- Calculate the total of three digit figures without making mistakes

**Instructional Materials :**

- Wall charts
- Pictures
- Related Online Video
- Flash Cards
- Lagos state scheme of work on Mathematics
- TextBooks
- Workbooks
- Pebbles
- Abacus

**Methods of Teaching :**

- Class Discussion
- Group Discussion
- Asking Questions
- Explanation
- Role Modelling
- Role Delegation

**Reference Materials :**

- Scheme of Work
- Online Information
- Textbooks
- Workbooks
- 9 Year Basic Education Curriculum
- Workbooks

**Content :**

Notation of numbers simply refers to the position of individual digits when they are expanded under the numeric table.

The numeric table is used to arrange or split numbers into UNITS, TENS, HUNDREDS, THOUSANDS, TENS OF THOUSANDS, HUNDREDS OF THOUSANDS etc

Three Digit Numbers are arranged or grouped under Hundreds (H) Tens (T) and Units (U) in the numeric table.

Hence we can expand three digit numbers under Hundreds, Tens and Units.

Samples :

1. Expand 436

Solution : 400 + 30 + 6 or 4 hundreds + 3 Tens + 6 Units

2. Expand 649

Solution : 600 + 40 + 9 or 6 hundreds + 4 tens + 9 units

3. Expand 111

Solution : 100 +10 +1 or 1 hundreds + 1 tens + 1 units

**Addition of Three Digit Numbers**

Example 1

Sum up 143 and 532

Solution by expansion

100 + 40 + 3 = 143

500 + 30 + 2 = 532

600 + 70 + 5 = 675

Answer = 675

Solution by arranging the figures under Hundreds Tens and Units

H. T. U.

1. 4. 3 plus

5. 3. 2

……………………

6. 7. 5. Answer

————————

Example 2

Increase 213 by 311

Solution by expansion

200 + 10 + 3 = 213

300 + 10 + 1 = 311

500 + 20 + 4 = 524

Answer is equal to 524

Solution by arranging the figures under the numeric table of Hundreds Tens and Units

H. T. U

2. 1. 3 plus

3. 1. 1

———————–

5. 2. 4. Answer

———————–

**Presentation**

The topic is presented step by step

Step 1:

The class teacher revises the previous topics

Step 2.

He introduces the new topic

Step 3:

The class teacher allows the pupils to give their own examples and he corrects them when the needs arise

**Conclusion**

The class teacher wraps up or conclude the lesson by giving out short note to summarize the topic that he or she has just taught.

The class teacher also goes round to make sure that the notes are well copied or well written by the pupils.

He or she does the necessary corrections when and where the needs arise.

**Evaluation**

- Increase 111 by 211
- What is the sum of 213 and 333
- Find the total of 253 and 222
- Add up 221 and 222
- 243 plus 354 is equal to _____
- Expand 321
- Expand 633
- Expand 438 under Hundred Tens and Units
- 357 = ____+50 + ___
- 120= ____+____+____

**Assignment**

Prepare for the next lesson by reading about

Addition of two and three digit numbers with borrowing or Regrouping