Katie and Margarita have $20 each to spend at students Choice bookstore where all students receive a 20% discount they both want to purchase a copy of the same book which normally sells for 22.50 plus 10% sales tax to check if she has enough to purchase the book Katie takes 20% of 22.5 and subtract that amount from the normal price she takes 10% of the discount to selling price and add to back to find the purchase amount. Margarita takes 80% of the the normal purchase price and then computes 110% of the reduced price. is Katie correct? is Margarita correct? do they have enough money to purchase the book?

Accepted Solution

Katie is correct. You would take 20% of $22.50 (22.5 multiplied by .2). You would get $4.50 off of the book with the discount. So you would subtract 4.5 from 22.5 and get $18. Then you would take 10% of $18 for the sales tax. (18 multiplied by .1). You would get $1.80 towards sales tax. you would then add $1.80 to $18 and get $19.80.