What is the power to another power rule

Can some one me with this math problem?

Using inductive reasoning, what are the next two number in this set? 2,3/2,4/3,5/4,

I'm at a bookstore with $\$35$ in my pocket and a $20\%$-off coupon. what is the cost of the most expensive book i can buy with my money and the coupon? (assume that there are books of every possible price in the bookstore. it's a large bookstore! )