Answer: 
<u>Switch operations</u>
Before: 
After: 
Before you switch operation you remove the subtraction sign where -(16) is.
2/7 because both 8 and 28 are divisible by 4
Well, if the notebooks cost x, then you know that
3x + 45.87 = 60.54
right? so, solve for x. 60.54 - 45.87 = 14.67
Divide the difference by 3.