Answer: Leanna ran 39.96 miles before she was passed by Irina.
Step-by-step explanation:
When Irina would pass Leanna, they would have ran the same distance.
Let t represent the time that Leanna ran before she was passed by Irina.
Distance = speed × time
Leanna started in group E and ran at a rate of 4.8 miles per hour. The distance ran by Leanna before she was passed by Irina is
4.8 × t = 4.8t
During the race she was passed by Irina who ran at a rate of 5 miles per hour and started in group H, 20 minutes(20/60 = 0.333 hour) after Leanna started. The time spent by Irina in running this distance is
t - 0.333
Distance ran by Irina is
5(t - 0.333) = 5t - 1.665
Since they ran the same distance, then
4.8t = 5t - 1.665
5t - 4.8t = 1.665
0.2t = 1.665
t = 1.665/0.2 = 8.325 hours
Therefore, the distance that Leanna ran before she was passed by Irina is
4.8 × 8.325 = 39.96 miles