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?

Both of them are correct. Margarita and Katie do have enough to purchase the books.

Step-by-step explanation:

Consider the provided information.

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.

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.

Let us find out whether Katie is correct or not.

She take 20% of 22.5 which is:

She subtract that amount from the normal price i.e = 22.5-4.5 = 18

She takes 10% of the discount to selling price:

And she add to back to find the purchase amount.

18 + 1.8 = 19.8

Which is the correct calculation.

Thus, Katie is correct.

Margarita takes 80% of the the normal purchase price and then computes 110% of the reduced price.

Let us find out whether Margarita is correct or not.

She take 80% of 22.5 which is:

Then she computes 110% of the reduced price.

Which is also the correct calculation.

Thus, Margarita is correct.

Both of them are correct. Margarita and Katie do have enough to purchase the books.

step-by-step explanation:

you can add the two numbers and divide the result by 2. or you can find the gap between the two numbers and add half of this to the smaller number.