Page 59 - ICSE Math 4

Exercise 5.5

1. Mul ply by la ce mul plica on.

(a) 35 × 18 (b) 68 × 92 (c) 841 × 46

(d) 245 × 32 (e) 268 × 195 (f) 423 × 202

2. Mul ply using both la ce and column methods.
(a) 23 × 45 (b) 56 × 23 (c) 824 × 32

(d) 456 × 17 (e) 132 × 144 (f) 345 × 221

Solving Word Problems

Example 7: A pet store has 15 tanks of tadpoles. If each tank has 46 Calcula ons
tadpoles, how many tadpoles does the pet store have? 3
4 6
Solu on: Number of tadpoles in 1 tank = 46
× 1 5
Number of tanks in the pet store = 15
2 3 0
Number of tadpoles in 15 tanks = 46 × 15 = 690
+ 4 6 0
So, there are 690 tadpoles in the tanks.
6 9 0
Framing Word Problems

Example 8: Frame two word problems for 3,432 × 6.
Solu on: 1. A baker sells 3,432 loaves of bread in a week. How many loaves does he
sell in 6 weeks?

2. A machine fi lls 3,432 cans in a day. How many cans does the machine fi ll in 6
days?

Mixed Problems

Example 9: A factory has 1,563 workers. There are 80 factory vans. If 8 workers travel in
each van, how many workers travel by other means of transport?
Solu on: Total number of workers in the factory = 1,563

Number of vans = 80 Calcula ons
015
Number of workers who travel in 1 van = 8 8 0 1 5 6 3
Number of workers who travel by vans = 80 × 8 = 640
× 8 – 6 4 0
Number of workers who travel by other means of
6 4 0 9 2 3
transport = 1,563 – 640 = 923

So, 923 workers travel by other means of transport.

49