Question

If 15% of 30% of 50% of a number is 90, then what is the number?

Answer 1

Eg. n is the number

15% × 30% × 50% × n = 90
15/100 × 30/100 × 50/100 × n = 90
3/20 × 3/10 × 1/2 × n = 90
n = 90 × 2/1 × 10/3 × 20/3
n = 180 × 10/3 × 20/3
n = 600 × 20/3
n = 4,000

The number is 4,000