Maths at a garage sale (not literally)

Last week I was learning about how important it is to read instructions properly and to look at the key in graphs.

Here are a few problems I worked on. It is important that I look at the key because it helps you with the question you're trying to figure out.  So the key in this grid is 6. 1 coin equals 6 dollars. So it’s obviously 6 x tables.  So it’s important to look at the key. That’s the first thing you do. Then you look at the question and figure it out.

                  Money Made at the Garage Sale

Monday
Tuesday
Wednesday
Thursday
Friday

Key: =  $ 6

How much money was made on Tuesday? $27

How much more money was made on Wednesday? $7.5

How much more money was made on Monday than Thursday? $12