$42 and if I'm not correct, you could then do your own homework for the right answer ðŸ“š.

# Suppose that a bookstore buys a textbook from the publisher for $50. At what price should the bookstore mark the textbook so that it may be offered at a discount of 20% but still give the bookstore a 40% profit on the $50 investment?

To obtain the desired 40% profit,

the book needs to sell for $50 + 40% * $50

Our target price for the sale is 50 + 0.4*50

= 50 + 20

=$70

We need the original price of the book

to be enough so that 20% off of that

price gives us $70

Set P = the original price

The original price minus 20% of the original price must equal $70

P - 20% * P = 70

P - 0.20P = 70

0.80P = 70

Divide each side by 0.80

P = 70/0.80

P = 87.5

So the books original price needs to be $87.5