On increasing the price of T.V. sets by 50%, their sale decreases by 20%. What is the effect on the revenue receipts of the shop ? Pick
A) 4  B) 5  C) 56  D) 20  E) 7
Explanation:   Let the price be = Rs.100, and number of units sold = 100   Then, sale value = Rs.(100 × 100) = Rs.10000   New sale value = Rs.(150 × 80) = Rs.12000   Increase% = 2000/10000 × 100 = 20%   Answer: 20
<result>D</result>
On increasing the price of T.V. sets by 50%, their sale decreases by 20%. What is the effect on the revenue receipts of the shop ?