Question

mario sketched a drawing of a dirt bike track he wants his dad to build. the brown area represents the track. Find the area of the track. round to the nearest tenth

Answer 1

brown area is the shaded area?

step 1

Find the area of the interior circle

`A=\pi\cdot r^2`

we have

r=20 ft

substitute

`\begin{gathered} A=\pi\cdot20^2 \\ A=400\pi\text{ ft2} \end{gathered}`

step 2

Find the area of the complete circle

r=35 ft

`\begin{gathered} A=\pi\cdot35^2 \\ A=1,225\pi\text{ ft2} \end{gathered}`

step 3

the shaded area is equal to the difference

`\begin{gathered} A=1,225\pi-400\pi \\ A=825\pi\text{ ft2} \end{gathered}`

assume pi=3.14

A=3.14*825=2,590.5 ft2

area is 2,590.5 square foot