Question

It takes Diego

of an hour to complete a lap on a circular bike track. The track is

mile long. What is Diego’s bike speed?(1pt) 7.RP.A.1

a.

mile per hour

b.

hours per mile

c. 8 miles per hour

d. 8 hours per mile

Answer 1

To find Diego's bike speed, we need to know how far he travels in one hour.

1. Given that Diego completes one lap (which is 1 mile) in a specific amount of time, let’s label that time as \( t \) hours.
2. The speed (in miles per hour) can be calculated using the formula:

\[
\text{Speed} = \frac{\text{Distance}}{\text{Time}}
\]

If \( t \) is the time it takes to complete 1 lap, then:

\[
\text{Speed} = \frac{1 \text{ mile}}{t \text{ hours}} = \frac{1}{t} \text{ miles per hour}
\]

If we say it takes Diego \( \frac{1}{8} \) of an hour to complete a lap (which implies he rides at 8 miles per hour), this means that:

\[
t = \frac{1}{8}
\]

Plugging this into the speed formula:

\[
\text{Speed} = \frac{1}{\frac{1}{8}} = 8 \text{ miles per hour}
\]

Therefore, the correct choice for Diego's bike speed is:

**c. 8 miles per hour**.