Final answer:
Lin takes 2.25 minutes to complete each lap around a track, calculated by dividing the total time of 9 minutes by the number of laps, which is 4.
Step-by-step explanation:
To calculate how many minutes per lap Lin runs, we need to divide the total time taken by the number of laps completed. Lin runs 4 laps in 9 minutes. Therefore, we divide 9 minutes by 4 laps to find the time taken per lap.
Minutes per lap = Total minutes / Total laps
Minutes per lap = 9 minutes / 4 laps
Minutes per lap = 2.25 minutes per lap
Thus, it takes Lin 2.25 minutes to run each lap around the track.