Gemma ordered four pizzas at $10 each, and she gave a $5 tip to the delivery person. How much change did she get back if she gives one fifty-dollar bill?
The cost of the four pizzas is 4 x $10 = $<T>multiply(4, 10)=40
The total cost, including the tip, is $40 + $5= $<T>add(40, 5)=45
Therefore, Gemma gets a change of $50 - $45 = $<T>subtract(50, 45)=5
