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Question

?Johnny's cafe serves desserts. One serving of ice cream and two servings of blueberry pie provides 790 calories. Three servings of ice cream and two servings of blueberry pie provides 1290 calories. Find the caloric content of each item.

Answer 1

Let C = ice cream and B = blueberry pie

then 3C + 2B = 1290c

 and 1C + 2B =   790c

 

subtracting equation 2 from equation 1, we get

2C = 500c, so C = 250c

solving for B, we get B = 270c

 

Proof: 3 x 250 + 2 x 270 = 750 + 540 = 1290