Page 56 - Whole Numbers (Addition and Subtraction)

Unit Whole nUmbers:
2 Addition And sUbtrAction

2.1 Practice

1. Write as little as possible to calculate, but write down your
final answer in each case.

(a) 80 + 50 + 40 + 30 + 70 + 80 + 90 + 20
(b) 800 + 500 + 400 + 300 + 700 + 800 + 900 + 200

(c) 300 + 500 − 400 + 600 − 500 + 700 − 600

(d) 1 300 + 1 500 − 400 + 1 600 − 500 + 1 700 − 600
(e) 2 300 + 2 500 − 400 + 2 600 − 500 + 2 700 − 600

(f) 1 300 + 1 500 − 1 400 + 1 600 − 1 500 + 1 700 − 1 600

(g) 2 300 + 2 500 − 2 400 + 2 600 − 2 500 + 2 700 − 2 600
2. Estimate roughly how much each of the following will be,
without rounding off the given numbers.

(a) 383 + 527 + 313 + 683 + 432 A set of numbers that

(b) 627 + 783 + 483 + 532 + 413 have to be added
together is called
(c) 632 + 513 + 727 + 883 + 583 a sum.
You see four different
(d) 613 + 732 + 983 + 827 + 683 sums in question 2.

3. (a) Calculate each sum in question 2
accurately.

(b) If your answers do not differ by 500 from one question to the
next, you have made mistakes. If so, correct your mistakes.

4. Calculate each of the following.
(a) 2 964 + 3 588 + 1 036 + 2 412

(b) 5 257 − 3 578 + 2 642 − 1 432

(c) 2 964 + 1 036 + 3 588 + 2 412
(d) 5 257 + 2 642 − 3 578 − 1 432

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