This is the only problem I need help with
Last summer Barry earned $875.This summer he earned 109% of what he earned last summer. How many more dollars did he earn this summer than he did last summer?
To start they give you last years earnings as $875
The amount Barry made this year was 109% of that.
The word "of" here indicates multiplication.
So, 109% * $875
The question is asking you how many more dollars, this is telling you that there is a difference (subtraction) between the two amounts.
This year - last year = Difference of this year and last year.
Now you just need to know that 109% converts to 1.09 in decimal form.
The equation is then
(1.09*$875) - $875 = $78.75