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3 years ago

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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 < 0.75 (B) 1.75< t < 2.0 (C) 2.0 < t < 2.5 (D) 2.5 < t < 3.0 (E) 3 < t < 3.5

1 answer:

Taya2010 [7]3 years ago

7 0

Answer:

The number of hours is 2.1.

(c) is a correct statement.

Explanation:

Given that,

Diameter = 2 miles

Average rate = 3 miles/hr

We need to calculate the time

Using formula of average rate

$Average\ rate =\dfrac{Total\ distance}{Total\ time}$

Put the value into the formula

$3=\dfrac{2\pi\times r}{t}$

$t=\dfrac{6.28}{3}$

$t = 2.1\ hr$

2.1 lies between 2.0 and 2.5.

Hence, The number of hours is 2.1.

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