Question

11. A board was cut into two pieces whose lengths are in the ratio 2:5. The longer piece was 45 cm.

How long was the shortest piece?

Answer 1

The shorter piece is 18 cm long.

Explanation:

A ratio can be written as a fraction. So, 2:5 can be written as
`(2)/(5)`

Let the shorter piece be x cm long.

This means:

`(x)/(45) = (2)/(5)`

If we cross multiply we get

5x = 2(45)

5x = 90

x = 18

Answer 2

Explanation:

2 : 5

x : 45

x=45x2/5

x=90/5

x=18