How many kg of dal costing ₹30 per kg must be mixed with 12 kg of dal costing ₹45 per kg so that the mixture is worth ₹36 per kg?

Explanation

1. 01

   Cheaper : dearer = $(45 - 36) : (36 - 30) = 9 : 6 = 3 : 2$.

2. 02

   2 parts = 12 kg, so 1 part = 6 kg.

3. 03

   Cheaper dal = $3 \times 6 = 18$ kg.