A number of boys raised Rs. 400 for a famine relief fund, each boy giving as many 25 paise coins as there were boys. The number of boys was -

A. 40

B. 16

C. 20

D. 100

Answer: Option A

Solution(By Examveda Team)

$$\eqalign{ & {\text{Let number of boys}} = x \cr & {\text{Number of 25 paise coins}} = {x^2} \cr & {\text{According to question,}} \cr & \frac{{{x^2}}}{4} = 400 \cr & {x^2} = 1600 \cr & x = 40\,\, \cr} $$