Question

If Mary walks in a perfect circle around a perfectly circular pond, approximately how far has she walked if the diameter of the pond is measured to be 48 feet and she has taken 3 laps around the pond? A. 144 B. 150 C. 450 D. 1800

Answer 1

Answer:  C. 450 feet

Step-by-step explanation:

Given : Diameter of perfectly circular pond= 48 feet

We know that the circumference of circle is given by :-

$C=\pi d$

Then, the circumference of pond will be :-

$C=(3.14)(48)=150.72\ feet$

Since,  she has taken 3 laps around the pond.

Then , the total distance covered by her = $3\times C$

$3\times150.72=452.16\approx450$  [Rounded to nearest tens.]

Hence, she walked 450 feet.

Answer 2

Answer: Option 'c' is correct.

Step-by-step explanation:

Since we have given that

Diameter of the pond = 48 feet

Radius of the pond = $\dfrac{48}{2}=24\ feet$

As we know the formula for "Circumference of circle":

So, Circumference of circle is given by

$2\pi r\\\\=2\times \dfrac{22}{7}\times 24\\\\=150.85\ feet\approx 150\ feet$

Number of laps around the lap  = 3

So, Distance she walked in 3 laps is given by

$150.\times 3\\\\=450\ feet$

Hence, Option 'c' is correct.