a. p = 8n - 30
Each item n is $8.
Expenses totaling $30 are subtracted.
So if the profit (p) is $170.00,
170 = 8n - 30
Now you need to solve.
Add 30 to both sides.
200 = 8n
Divide both sides by 8.
25 = n
25 items were bought.
b. If 25 items were bought, but the expenses were instead $40, what would be the total profit?
p = 8(25) - 40
p = 200 - 40
p = 160
The profit decreased by 10.
