instead of ... write a digit to be able to reduce the fraction 12.../23... .if there are 2...sin the same fraction, replace them with the same digit. Find all possible ...s

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! )