the second number = 40
Explanation:
The given ratios: 3:12,4:16 and 5:20
when we break them to simplest form:
3:12 = 1: 4
4:16 = 1: 4
5:20 = 1: 4
This means the second number is four times the first number
if the first number = 10
the second number = 4 times 10 = 4 × 10
the second number = 40
To check: when we break down 10:40 to simplest form, we must get 1: 4 (equivalent ratio)
10: 40 = 1: 4
Therefore, the second number = 40
