### The marked price of a radio is 20% more than its cost price. If a discount of 10% is given on the marked price, the gain per cent is:

A. 15 B. 12 C. 10 D. 8 Answer: Option D
Let CP = 100 Then, MP = 100 + 20% of 100 = 120 Now, SP = 120 – 10% of 120 = 108 Gain = 108 – 100 = 8 %Gain $\Large=\frac{8 \times 100}{100}$ = 8% Short-cut 100(CP) == 20%(up) ⇒ 120(MP) == 10%(disc.) ⇒ 108 % gain = 8%