Page 60 - ICSE Math 4

Exercise 5.6

1. Solve the given word problems.

(a) Rachita has 9 packets of s ckers with 125 s ckers in each. How many s ckers
does she have altogether?
(b) Hari and Noni join swimming classes during their summer vaca ons for a
month. The fees for swimming classes is ` 1,350 per person for 1 month. They
give ` 3,000 to the instructor. How much money should they get back?

(c) A school has 2,146 students. There are 14 school buses. If 85 students travel in
each bus, how many students come to school by other means of transport?

(d) Anil reads 26 pages in a day. How many pages will he read in 9 days?
(e) 63 bags are fi lled with coins. There are 352 coins in each bag. How many coins
are there in all?

2. Frame two word problems for each of the following and solve them.

(a) 270 × 24 (b) 123 × 35 (c) 298 × 156
Multiplication by Expanded Form

We have already learnt how to mul ply a 2-digit number by a 1-digit number using the
expanded form. Let’s learn how to mul ply a 3-digit number by a 1-digit number using the
same method.

Example 10: Find the product of 325 and 9 using the expanded form.

Solu on: Step 1: Write the mul plicand in its expanded form.
325 × 9 = (300 + 20 + 5) × 9

Step 2: Mul ply each term of the expanded form by the mul plier.

(300 + 20 + 5) × 9 = (300 × 9) + (20 × 9) + (5 × 9)
= 2,700 + 180 + 45

Step 3: Add the products obtained.

2,700 + 180 + 45 = 2,925
So, 325 × 9 = 2,925.

Estimating Product of Two Numbers

We know that es ma ng product means fi nding an approximate value of the product of

two numbers by rounding off the mul plicand and the mul plier to the nearest 10; 100;
1,000, and so on.

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