Method 1:
Quantity×Rate=Price
Given : Q1= 60
R1 =r
P1= p
Q2=q
R2=1.44r
P2=1.2p
Hence Q=50
So the difference in price is 50.
Method 2:
Let the price per kg of wheat = Rs 10, hence total expenditure initially = Rs 600
The expenditure increases by 20% = Rs 720
Also, the price increases by 44% , hence price per kg = 14.4
Thus, new consumption =72014.4 = 50 kgs. the diffrence in consumption is 60-50= 10 kg. Option (a)