Question

what is the surface area of this cone? use π ≈ 3.14 and round your answer to the nearest hundredth. 15 in 4 in square inches submit

Explanation:

Step1: Recall the formula for the surface area of a cone

The surface area \( S \) of a cone is given by the formula \( S=\pi r(r + l) \), where \( r \) is the radius of the base and \( l \) is the slant height of the cone. From the diagram, we know that \( r = 4 \) inches and \( l=15 \) inches, and \( \pi\approx3.14 \).

Step2: Substitute the values into the formula

Substitute \( r = 4 \), \( l = 15 \) and \( \pi\approx3.14 \) into the formula:
\[

$$\begin{align*} S&=3.14\times4\times(4 + 15)\\ &=3.14\times4\times19 \end{align*}$$

\]

Step3: Perform the multiplication

First, calculate \( 4\times19 = 76 \). Then, multiply by \( 3.14 \):
\[
S=3.14\times76 = 238.64
\]

Answer:

\( 238.64 \)