Answers:
- Pizza Uno = $5.25
- Pizza Duo = $5.60
Those are the costs for a whole small pizza.
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Explanation:
Let
- x = cost of whole small pizza from Pizza Uno
- y = cost of whole small pizza from Pizza Duo
x and y are some dollar amount, so they cannot be negative numbers. It also doesn't make sense to have them be 0 either. So we'll make them positive.
2/3 of x is equal to 3.50 as the first sentence mentions. This forms the equation (2/3)*x = 3.50
Multiply both sides by the reciprocal of 2/3 to isolate x
(2/3)*x = 3.50
(3/2)*(2/3)*x = (3/2)*3.50
x = 5.25
Pizza Uno charges $5.25 for a whole small pizza.
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Pizza Duo charges $4.20 for 3/4 of a small pizza, meaning the equation we need to solve is
(3/4)y = 4.20
We'll use the same idea as the last equation to get...
(3/4)y = 4.20
(4/3)*(3/4)y = (4/3)*4.20
y = 5.60
Pizza Duo charges $5.60 for a whole small pizza.
Pizza Uno is the better deal (assuming both pizzas taste the same or you don't have a preference for either). You would save $5.60 - $5.25 = $0.35 = 35 cents.
