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I need help with this question please help

I need help with this question please help-example-1

1 Answer

3 votes

Answer:

282.857 in²

Explanation:

The formula of a surface area of a cylinder:


S.A.=2\pi r^2+2\pi rH

r - radius

H - height

We have:

r = 5 in

H = 4 in

Substitute:


S.A.=2\pi(5^2)+2\pi(5)(4)=2\pi(25)+2\pi(20)\\\\=50\pi+40\pi=90\pi\ in^2


\pi\approx(22)/(7)

Substitute:


S.A.\approx90\cdot(22)/(7)=(1980)/(7)\approx282.857\ in^2

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