Pure ghee costing Rs.100 per kilogram and vegetable oil costing Rs.50 per kilogram are mixed in some ratio and sold at Rs.96 per kilogram so as to gain 20%. In what ratio is ghee and oil mixed?

Cost of pure ghee= Rs.100 per kg

After adulteration cost of ghee = Rs.50 per kg

Selling price of mixture = Rs.96 per kg

Profit=20%

To find the ratio of the mixture

 profit = $$96\times \frac{20}{100}$$

=approx. RS 19

 cost price=selling price - profit

=96-19

= RS 77

Rounding off to nearest 10 that is 77=80

Now by using the allegation rule we have

Cost of 1 kg ghee = 100, cost of 1 kg vegetable oil=50

Cost price =80

Hence 80-50=30

So 100-80=20

=30:20

=3:2