GMAT PREP??

[dferm]

A circular jogging track forms the edge of a circular lake that has a diameter of 2 miles. Johanna walked once around the track at the average rate of 3 miles per hour. If t represents the number of hours it took Johanna to walk completely around the lake, which of the following is a correct statement?

A. 0.5<t<.075
B. 1.75<t<2.0
C. 2.0<t<2.5
D. 2.5<t<3.0
E. 3<t<3.5

PLEASE EXPLAIN...

[tmmyc]

For this, we use d = r*t

Johanna walked around the lake once, so her total distance is the circumference of the circular lake.

diameter = 2
radius = 1
circumference = 2*pi*r = 2*pi

Next, we are given her rate: 3 miles per hour

Plug the values into the formula
d = r * t
-> 2*pi = 3*t
--> (2*3.14)/3 = t
---> t = 2.09

Answer is C.