By selling 12 apples for a rupee, a man loses 20%. How many for a rupee should he sell to gain 20%

SP = 100/12 paise Lets CP = x SP = 0.8x = 100/12 ∴ x = 10/(0.8x12) paise Therefore, CP = 100/9.6 paise Thus the new SP (with 20% profit) = 100/9.6 X 1.2 = 100/8 paise Hence, 8 apples can be purchased for Rs.1 to gain 20%