A vending machine sells chips at $0.55 and candy at $0.75. Last month the vending machine yielded at $189.00 with the sale of 280 items. How many packages of chip were purchased last month?
Solve the system of equations by eliminating one variable.
0.55x + 0.75y = 189 0.55x + 0.55y = 154
Multiply the whole second equation by 0.55 so both x's in both equations have the same value. Then subtract the second equation from the first so you're left with:
0.2y = 35 y = 175
Sub this y-value back into either equation to get x.
