Question

The total surface area of a cylinder is 690.8 inches. Its diameter is 10inches. What is the height? Use 3.14 for

Answer 1

We have that the formula for the surface area of a cylinder is the following:

`S=2\pi rh+2\pi r^2`

in this case, we have the following:

`\begin{gathered} S=690.8 \\ d=10\Rightarrow r=5 \\ \pi=3.14 \\ \Rightarrow690.8=2(3.14)(5)h+2(3.14)(5)^2 \\ \Rightarrow690.8=31.4h+157 \\ \Rightarrow31.4h=690.8-157=533.8 \\ \Rightarrow h=(533.8)/(31.4)=17 \\ h=17 \end{gathered}`

therefore, the length of the height is 17 inches