The ratio of two number is 3 : 5. If their product is 3375, then what is the sum of both the numbers?

a) 75
b) 120
c) 90
d) 135

Ans : 120

SSC Constable GD paper : Elementary Mathematics

Solution :

The ratio of two number is 3 : 5
Number are 3x and 5x

Product of numbers is 3375
$ 3x \times 5x = 3375 $
$ x^2=225, x=15 $

Sum of both the numbers = $ 3x +5x = 8x = 8\times15 =120 $