Question

Three-quarters of a number is 15.
Work out four-fifths of the number.

Answer 1

16

Step-by-step explanation:

let the number be x , then

\frac{3}{4} x = 15 ( multiply both sides by 4 to clear the fraction )

3x = 60 ( divide both sides by 3 )

x = 20 , then

\frac{4}{5} × 20 = 4 × 4 = 16

Answer 2

16

Explanation:

let the number be x , then

`(3)/(4)` x = 15 ( multiply both sides by 4 to clear the fraction )

3x = 60 ( divide both sides by 3 )

x = 20 , then

`(4)/(5)` × 20 = 4 × 4 = 16