Type the correct answer in the box. Use numerals instead of words. If necessary, use / for the fraction bar. Consider functions f and g.

Evaluate the function composition.

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! )