Page 54 - ICSE Math 5

Exercise 4.3

1. Divide using long division method. Also, check the answer.

(a) 563  24 (b) 987  13 (c) 359  31 (d) 482  21
(e) 5,981  18 (f) 6,325  15 (g) 4,060  14 (h) 9,302  20

2. Divide using the cancellation method.
(a) 360 ÷ 30 (b) 7,050 ÷ 50 (c) 5,600 ÷ 400

(d) 4,500 ÷ 900 (e) 88,000 ÷ 2,000 (f) 36,000  6,000

3. Divide using breaking a number and then dividing method.

(a) 9,650  10 (b) 4,680 20 (c) 8,550  50

(d) 7,525  25 (e) 9,630  30 (f) 4,980  20

Estimating the Quotient

We have already learnt how to estimate the sums, differences and products of the given numbers.
Now let’s learn to estimate the quotient.

Estimating the quotient means rounding off the dividend and the divisor to the nearest 10 and
then dividing the rounded off numbers to obtain the quotient.

Example 17: Estimate the quotient of 8,346  17.
Solution: 8,346  17

Round off the dividend and the divisor to the nearest 10.

8,346  8,350 (Rounded off to the nearest 10)

17  20 (Rounded off to the nearest 10)

Actual division Estimated division

490 417
17 8346 20 8350
– 68 – 80

154 35
– 153 – 20
16 150
– 0 – 140

16 10

So, the estimated quotient is 417.

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