Use the description to find the constant of proportionality. The constant of proportionality is square square It took Eleni 40 minutes to run 8 laps around the track.

To find the constant of proportionality, we need to determine the rate at which Eleni runs laps. The constant of proportionality in this case is the number of laps Eleni runs per minute.<br /><br />Given:<br />- Eleni runs 8 laps in 40 minutes.<br /><br />We can find the constant of proportionality by dividing the number of laps by the number of minutes:<br /><br />\[<br />\text{Constant of proportionality} = \frac{\text{Number of laps}}{\text{Number of minutes}} = \frac{8 \text{ laps}}{40 \text{ minutes}} = \frac{8}{40} = \frac{1}{5} \text{ laps per minute}<br />\]<br /><br />So, the constant of proportionality is:<br /><br />\[<br />\boxed{\frac{1}{5}}<br />\]