Question

Sonu buys 40 kg of wheat at ₹ 12.50 per kg and 30 kg of wheat at ₹ 14 per kg. At what rate per kg should he sell the mixture to gain 5% on the whole?

Answer 1

40 kg of wheat is bought for ₹12.50/kg.
∴ CP of 40 kg of wheat = 40 × 12.50 = ₹500
30 kg of wheat is bought for ₹14/kg.
∴ CP of 30 kg of wheat = 30 × 14 = ₹420
Total CP = ₹500 + ₹420 = ₹920
Profit = 5% of CP = 5% of ₹920 = $\frac{5}{100}\times 920=₹46$
Let the SP be ₹x.
Profit = SP − CP
⇒ x − 920 = 46
⇒ x = ₹966
SP of 70 kg wheat = ₹966
∴ SP of 1 kg wheat = $\frac{966}{70}=₹13.80$
Thus, the selling price of the mixture is ₹13.80/kg.