Question

Maria and Edwin have $23.00 each to spend at a book fair, where all students receive a 25% discount. They both want to purchase a copy of the same book, which normally sells for $26.50 plus 10% sales tax. To check if she has enough to purchase the book, Maria takes 25% of $26.50 and subtracts that amount from the normal price. She takes 10% of the discounted selling price and adds it back to find the purchase amount. Edwin takes 75% of the normal purchase price and then computes 110% of the reduced price. Is Maria correct? Is Edwin correct? Do they have enough money to purchase the book? Explain your answer using complete sentences, and show your work.

Answer 1

Maria : 26.50 - 0.25(26.50) = 26.50 - 6.625 = 19.88
            19.87 + 0.10(19.87) = 19.87 + 1.99 = 21.86

Edwin : 0.75(26.50) = 19.88
             1.10(19.88) = 21.86

and if they each have $ 23, then yes, they both ave enough money to buy the book. They both were correct in their calculations. Because taking 25% off, is the same as paying 75%.....and taking the discount price and subtracting 10% from that, is the same as multiplying by 110%. So they basically worked the same problem, just in a little different way...and they both ended up with the same answer