Explanation:
jogger 2 will overtake the first at the moment both were running the same distance.
speed is distance/time.
so, when we multiply speed by time we get distance.
the first jogger gets a head start and runs for ten minutes with 4 mph.
10 minutes is 10/60 = 1/6 of an hour.
so, he is running
1/6 × 4 = 4/6 = 2/3 miles in these 10 minutes.
from that moment on both are running for the same time (let's call it x) just with different speeds.
remember the key moment is, when both have run the same distance.
x × 5 mph = x × 4mph + 2/3 miles
5x = 4x + 2/3
x = 2/3 hours = 2/3 × 60 = 120/3 = 40 minutes
so, it will take the second jogger 40 minutes to overtake the first jogger.