Answer: $80
Explanation:
You have been told that Sarah ended up paying $60, and you were told before that the charge for a lost book was 75%.
Therefore
$60 = 75%
Now we have to find out what amount of money would be equivalent to 100%:
To do this, find out what amount of money would be equivalent to 25% first.
You can do this by dividing both values by 3.
60 / 3 = 20
75 / 3 = 25
So now $20 = 25%
Now find 100% (which is the original amount) multiply each value by 4 :
$80 = 100%
So the school payed $80 for the book.
hope this helps :)