Given:A wholesaler bought walnuts and peanuts, the price of walnut per kg being thrice that of peanut per kg. He then sold 8 kg of peanuts at a profit of 10% and 16 kg of walnuts at a profit of 20% to a shopkeeper.
However, the shopkeeper lost 5 kg of walnuts and 3 kg of peanuts in transit. He then mixed the remaining nuts and sold the mixture at $166 per kg, thus making an overall profit of 25%.
Asked: At what price, in $ per kg, did the wholesaler buy the walnuts?
Let the purchase price of walnuts and peanuts be w & p $/kg respectively
w = 3p
Purchase price of 8 kg of peanuts for shopkeeper after wholesaler sold at a profit of 10% = 1.1*8p = 8.8p
Purchase price of 16 kg of walnuts for shopkeeper after wholesaler sold at a profit of 20% = 1.2*16w = 1.2*48p = 57.6p
However, the shopkeeper lost 5 kg of walnuts and 3 kg of peanuts in transit.
Remaining walnuts = 16 - 5 = 11kg
Remaining peanuts = 8 - 3 = 5 kg
Remaining mixuture = 11 + 5 = 16 kg
Overall profit = 25% (8.8p + 57.6p) = 166*16 - (8.8p + 57.6p)
1.25 (8.8p + 57.6p) = 166*16
p = 32
w = 3*32 = 96
IMO D