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User Apache
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1 Answer

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24 votes

Answer:

Total surface area=

304+9pi

~= 332.3

Explanation:

Surface area is the areas of all the parts/sides/surfaces of the shape all added together.

There is a BOTTOM, 4 SIDES, a flat TOP, and a DOME shape.

The BOTTOM and SIDES are rectangles, so you can get the areas by multiplying length × width (or b•h)

BOTTOM: 8×10 =80

SIDES: There are 4×8 sides. 4×8 = 32. There are two of them 2×32=64.

There are 4×10 sides. 4×10 = 40. There are two of them, 2×40 = 80

For the flat TOP, it is also 8×10=80, but it has a circle cut out of it. Or, well, the circle that's under the dome doesn't count bc of the dome. So we'll take it away.

CIRCLE (under the dome):

Area of a circle is A=pi•r^2= pi•3^2

A = 9pi

So the flat TOP is:

80 - 9pi ~= 51.7

The DOME is a hemisphere (a half ball shape). Surface Area of a sphere is 4pi•r^2 We find that, then take half.

DOME =

4pi•3^2•(1/2)

= 4pi•9•(1/2)

= 18pi

~= 56.5

Now add up all the pieces:

80+64+80+80-9pi+18pi

= 304+9pi

~= 304 +28.3

= 332.3

User Jayanth
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