Question

In 90 minutes, John can run 30 laps around the track. Determine the number of laps he can run per hour.
20 laps/hour
10 laps/hour
30 laps/hour
40 laps/hour

Answer 1

To determine how many laps John can run per hour, we start by calculating the number of laps he runs in one minute.

Since John runs 30 laps in 90 minutes, we can calculate his laps per minute as follows:

\[
\text{Laps per minute} = \frac{30 \text{ laps}}{90 \text{ minutes}} = \frac{1}{3} \text{ laps per minute}
\]

Next, we need to find out how many laps he runs in one hour (60 minutes):

\[
\text{Laps per hour} = \left(\frac{1}{3} \text{ laps per minute}\right) \times 60 \text{ minutes} = 20 \text{ laps per hour}
\]

Thus, John can run **20 laps per hour**.

The correct answer is:
**20 laps/hour**.