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Question: Find the surface area of each figure. Round the answer to two decimal places. (use π = 3.14) Do not include units of measure in your answer.

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I need help! By this afternoon! I would appreciate it:) Question: Find the surface-example-1
User Juwon
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1 Answer

6 votes

Answer:

SA ≈ 340.26 cm²

Explanation:

We have the rectangular prism 6cm × 10cm × 6cm and the semisphere with diameter D = 6cm → radius R = 3cm (6 : 2 = 3).

The surface area of given figure:

Surface area of a rectangular prism reduced by an area of a circle

+

Half of surface area of a sphere.

The formula of a surface area of

a reactangular prism:
SA=2(lwlh+wh)

a sphere:
SA=4\pi R^2

The formula of an area of a circle:
A=\pi r^2

The surface area of a rectangular prism:


l=6cm,\ w=10cm,\ h=6cm


SA_1=2(6\cdot10+6\cdot6+10\cdot6)=2(60+36++60)=2(156)=312\ cm^2

The surface area of a sphere:


R=3cm


SA_2=4\pi(3^2)=4\pi(9)=36\pi\ cm^2

The area of a circle:


r=3cm


A=\pi(3^2)=9\pi\ cm^2

The surface area of figure:


SA=SA_1-A+(1)/(2)SA_2

Substitute:


SA=312-9\pi+(1)/(2)(36\pi)=312-9\pi+18\pi=(312+9\pi)\ cm^2


\pi\approx3.14


SA\approx312+9(3.14)=312+28.26=340.26\ cm^2

User Kviksilver
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