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what is the surface area of the cone used 3.14 as pi his pencil and paper supposed to diameter and the slant height of a cone are cut in half how does this affect the surface area of the cone

what is the surface area of the cone used 3.14 as pi his pencil and paper supposed-example-1
User SkyFox
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1 Answer

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16 votes

EXPLANATION

The area of a cone is given by the following relationship:


\text{Area}_{\text{cone}}=\pi\cdot r^2+\pi\cdot r\cdot s\text{ where s is the diagonal and r is the radius}

Replacing terms and using 3.14 as pi:


\text{Area }=\text{ 3.14}\cdot(5)^2+\pi\cdot5\cdot15
\text{Area}=\text{ 3.14}\cdot25+75\cdot3.14

Multiplying terms:


\text{Area}=78.5+235.5

Adding numbers:


\text{Area}=314cm^2

User Andrei Bardyshev
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