Page 82 - ICSE Math 6

4
Example 24: If of a number is 16, then what is the number?
5
4
Solution: of the number = 16
5
4
\ × Number = 16
5

⇒ Number = 16 ÷ 4
5
5 4 16 ×5
Number = 16× = = 20
4 4 1

Thus, the required number is 20.

EXERCISE 5.3

1. Add the following.

(a) 4 + 9 (b) 1 + 6 (c) 7 + 2 (d) 11 + 5
5 5 7 7 9 18 13 26

2 5 4 6 11 5 6 3 1 1 11
(e) + + (f) + + + (g) 1 + 12 (h) 5 + 5 +
3 12 9 7 21 14 14 5 5 15 10
3 1 11 3 2 1 2 2 5 1
(i) 2 1+ + 2 (j) 6 + 2 (k) 5 + 3 + 2 (l) 6 + + 1 + 2
4 6 14 7 3 3 9 3 9 6
2. Simplify.

9 3 2 1 5 3 3 5
(a) – (b) – (c) – (d) 1 −
5 5 7 14 4 8 7 28
3 2 21 60 7 9 5 5
(e) 7 –4 (f) 16 − 15 (g) 5 − 2 (h) 2 − 1
5 3 25 75 20 40 14 7
5 5
3. What number should be added to to get 1 ?
14 7
1
4. What number should be subtracted from 3 to get 2 ?
3
4 2
5. A m long rope is cut into two parts. If one part is of length m, find the length of the other
5
part. 3
6. Multiply.

1 9 5 1 9 1 4 25
(a) 1 by (b) 5 by1 (c) by 2 (d) by
3 16 7 20 11 5 5 16

7. Simplify.

1 9 5 3 15 2 1
(a) 2 ×4× (b) 1 ×6×1 (c) × ×1
3 14 16 10 16 5 5
5 25 2 4 5 3
(d) ÷ (e) 6 ÷ 4 (f) 1 ÷ 1
4 16 3 9 16 4

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