Page 22 - Whole Numbers (Addition and Subtraction)

2. Two numbers are given in expanded notation below. Add the
two numbers and write the answer as a single number.

The numbers are 400 + 30 + 4 and 300 + 50 + 3.

3. Calculate 364 + 678.

To calculate 458 + 276 you may break down the numbers and
work with the parts, then build up the answer:
Break down:

458 = 400 + 50 + 8 and 276 = 200 + 70 + 6
Work with the parts:
400 + 200 = 600 50 + 70 = 120 8 + 6 = 14

Build up the answer:
600 + 120 + 14

100
= 700 + 20 + 14

10
= 700 + 30 + 4
= 734

4. Calculate.

(a) 239 + 456 (b) 387 + 288
(c) 368 + 446 (d) 532 + 234

Two different ways to calculate 734 − 568 are shown below.

A. The filling-up or add-on method
To calculate how much 734 − 568 is you may ask yourself how
much you must add to 568 to reach 734.

You may then do this in steps as shown below.
568 + 32 → 600 + 134 = 734
You had to add 32 and 134 which is a total of 166.
So 734 − 568 = 166.

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