Original cost of the book = $25
Percentage of discount got by Marilyn while buying the book = 15%
Amount of discount got by Marilyn while buying the book = (15/100) * 25
= 375/100
= 3.75 dollars
So
The amount paid by Marilyn for buying the book = (25 - 3.75) dollars
= 21.25 dollars
So the total amount paid by Marilyn for buying the book is $21.25.
I hope the procedure for doing this problem is clear to you.
