Some fruits are bought at 20 for Rs.160 and an equal number of fruits at 15 for Rs.140. If all the fruits are sold at Rs.144 per dozen, then what is the profit percent in the entire transaction?

Let total fruit brought be LCM of 20 and 15 = 60 So, let 60 fruits are bought at 20 for Rs. 160, then cost of 60 fruits = 160/20 × 60 = Rs. 480 ⇒ 60 fruits are also brought at 15 for Rs. 140, then cost of 60 fruits = 140/15 × 60 = Rs. 560 ⇒ Total cost of 120 fruits = Rs. 480 + Rs. 560 = Rs. 1040 SP of 12 fruits = Rs. 144 ⇒ SP of 1 fruit = Rs. 12 ⇒ SP of 120 fruits = Rs. 12 × 120 = Rs. 1440 Profit = SP - CP = Rs.1440 - Rs. 1040 = Rs. 400 Profit percent = 400/1040 × 100 = 38.46%