Question

Amy and Heather want to run a 1-lap race around a circular track. One lap in Heather's lane measures 400 m. Amy is in the outside lane, which is two meters farther from the center of the track than Heather's lane.

Answer 1

Circumference is 400m

The circumference is the perimeter of a circle is

`Circumference\text{ of a circle = 2}\pi r`

To find the radius since the circumference is given as 400

Make radius the subject of the formula

`\text{Radius of first circle }(400)/(2\pi)`

`\text{Radius of first circle }(400)/(2*3.142)=(400)/(6.284)=63.654`

Now the radius of the big circle

It is plus 2

`63.654\text{ +2=65.65}4`

The circumference of big circle is

`\begin{gathered} \text{The circumference of big circle =2}\pi r \\ \\ \text{The circumference of big circle =2}*3.142*65.657 \\ \text{The circumference of big circle =412.5697} \end{gathered}`

Finally

`412.56-400=12.56`

The final answer

`12.56`