Question

A bookseller sells a book for Rs. 100, gaining Rs. 20. His gain per cent is 

A. 20% 

B. 25% 

C. 22% 

D. none of these

Answer 1

SP = Rs.100 

Gain = Rs.20 

CP = SP – Gain 

= 100 - 20 

= Rs.80

\(Gain\%=\frac{Gain\,\times\,100}{CP}\)

= \(\frac{20\,\times\,100}{80}\)

= 25%