Hi!
As you can see from the examples, it is taking the value of the type of coin, and multiplying it by the amount of the coin. So pretty simple.
7.
A nickel value is 0.05
0.05(x+7)
9.
A $20 bill value is 20
20(4y)
11.
A $50 bill value is 50
50(35-x)
Hope this helps! :)
