Question

Ade has two similar scale models of the same pyramid. The first model has a

height of 5 inches and a surface area of 80.9 square inches. The linear dimensions
of the second model are each increased by a common factor so that the height of
the second model is 15 inches. To the nearest tenth of a square inch, what is the
surface area of the second model?

Please help!

Answer 1

Answer: 242.7 square inches

Explanation:

Hi, to answer this question we have to apply proportions:

The first model has a height of 5 inches and a surface area of 80.9 square inches:

The proportion is : height/ surface area= 5 in / 80.9 in2

For a height of 15 inches

15 in/ x in2

So:

5/80.9 = 15/x

x= 15/ (5/80.9 )

x= 242.7 square inches

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