Question

Scott likes to run long distances. He can run 20 \text{ km}20 km20, start text, space, k, m, end text in 858585 minutes. He wants to know how many minutes (m)(m)left parenthesis, m, right parenthesis it will take him to run 52 \text{ km}52 km52, start text, space, k, m, end text at the same pace.
How long will it take Scott to run 52 \text{ km}52 km52, start text, space, k, m, end text?
minutes

Answer 1

Answer:

221 min

Step-by-step explanation:

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Answer 2

Answer:

Scott will take 221 minutes to run 52 km

Step-by-step explanation:

Speed

The speed of an object can be calculated with the formula:

$\displaystyle v=\frac{d}{t}$

Where d is the distance traveled and t is the time taken.

Scott can run d=20 km in 85 minutes. Thus, his speed is:

$\displaystyle v=\frac{20}{85}\ km/min$

Now he wants to know how many minutes it will take him to run d=52 km. Solving the formula for t:

$\displaystyle t=\frac{d}{v}$

Since the speed has been already determined:

$\displaystyle t=\frac{52}{\frac{20}{85}}$

Multiplying by the reciprocal of the denominator:

$\displaystyle t=52*\frac{85}{20}$

t = 221 min

Scott will take 221 minutes to run 52 km