You bought two varieties of rice, costing 5 cents per ounce

Question

and 6 cents per ounce each, and mixed them in some ratio. You then

sold the mixture at 7 cents per ounce, making a profit of 20 percent.

What was the ratio of the mixture?

Answer 1

let's say that for each ounce of 5-cent rice, you buy k ounces of 6-cent rice.

7(1+k) = (5+6k)(6/5)
k = 5