In what ratio must a person mix three kinds of wheat costing him Rs.1.20/kg, Rs.1.44/kg and Rs.1.74/kg, so that if he keeps the price of the mixture as Rs.1.41 per kg, he has neither profit nor loss?

The correct option is (B)

12:7:7

1^st wheat 2^nd wheat 3^rd wheat

120 144 174

Following the above rule, we have,

$\text{Therefore, the required ratio is}36:21:21=12:7:7$