You return a book to the library that is 6 days overdue. The library charges a flat fee of $.90 plus a fee for everyday that the book is late.If your total fees are $2.40, how much are the daily fees?

Answer 1

You start with what you know:

Flat fee: 0.90

Days late: 6

Sum of fees: 2.40

What do you want to know?

Daily fee, we will call this unknown number x

To get the sum of what you have to pay, you will have to calculate how often you have the daily fee, which is six times, because it was six days late: 6 times X, or 6X

You also have to add the flat fee of 0.90: 6X + 0.90

And that equals what you had to pay: 6X + 0.90 = 2.40

Now you solve it for X, because you are looking for this unknown number. Your first step is to make the 0.90 go away on the left side. You can do that by subtracting 0.90, but what you do on one side, you also do on the other side (otherwise it would not be equal):

6X + 0.90 - 0.90 = 2.40 - 0.90

Calculate, and you will get:

6X = 1.50

Now we have to get rid of the 6 on the left, and we can do that by dividing the left side by 6, and we do the same thing to the right side as well.

6X/6 = 1.50/6

Calculate: X = 1.50/6.... put it in the calculator and you will have your answer.

Answer 2

We can assume that the daily fee is x dollars. Since the book is 6 days overdue, then the library charges an overdue fee for 6 days that is 6x dollars. So the total fee charged by the library is the overdue fee (6x dollars) plus the flat fee (0.9 dollars); note that this 0.9 dollar fee is only charged one time. As we know the total fee is 2.4 dollars, then we can have the following equation:

6x + 0.9 = 2.4

6x = 1.5 (Subtract 0.9 on both sides)

x=1.5/6 =0.25 (Divide 6 on both sides)

Now we can conclude that the daily fee is 0.25 dollars.