Page 49 - ICSE Math 5

2. Multiply the following numbers.
(a) 1,263 × 56 (b) 2,014 × 69 (c) 5,203 × 705

(d) 4,897 × 831 (e) 8,231 × 3,410 (f) 9,806 × 2,901

3. Find the product.

(a) 5,935 × 10 (b) 3,641 × 100 (c) 32,522 × 900
(d) 1,114 × 3,000 (e) 2,059 × 40 (f) 1,798 × 6,000

4. Multiply using lattice multiplication method and verify the result by simple
multi plication.

(a) 3,120 × 48 (b) 6,153 × 83 (c) 7,924 × 54
(d) 1,876 × 70 (e) 4,031 × 99 (f) 9,212 × 636

5. Multiply using expanded form and check your answer by actual multiplication.

(a) 2,409 × 62 (b) 1,786 × 131 (c) 1,089 × 1,276

(d) 2,368 × 201 (e) 4,056 × 98 (f) 7,001 × 1,428
Estimating the Product

Estimating product means finding an approximate value of the product of two numbers by
rounding them to the nearest 10; 100; 1,000; and so on. By using the method of estimation in
multiplication, we can find a product quickly. The product obtained will only be an approximate
estimation and will differ from the actual product.
Example 10: Estimate the product of 3,075 and 216 by rounding off the numbers to the nearest
100.

Solution: To estimate the product, round off 3,075 and 216 to the nearest 100.

3,075  3,100 (Rounded off to the nearest 100)
216  200 (Rounded off to the nearest 100)

Now multiplying the rounded off numbers, i.e., 3,100 and 200, we get 6,20,000.
So, the estimated product is 6,20,000. It is read as six lakh twenty thousand.

Word Problems on Multiplication

Example 11: A factory produces 6,492 cushions in a week. How many
Calculation
cushions will the factory produce in twelve weeks?
1
Solution: Number of cushions produced in a week = 6,492 6492

Total number of cushions that will be produced in 12 weeks × 1 2
1 1
= 6,492 × 12 = 77,904 12984
So, the factory will produce 77,904 cushions in 12 weeks. +64920
77904

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