Answer:
At 8:52:30 am they will be side-by-side again
Step-by-step explanation:
Let s be the distance ran in one 1 lap.
Here Jeff runs one extra lap compared to Mandy for coming side by side again.
Mandy runs one lap in 2 minutes and 30 seconds = 150 s
Speed of Mandy, [tex]=\frac{s}{150}[/tex]
Jeff runs one lap in 2 minutes and 15 seconds = 135 s
Speed of Jeff, [tex]=\frac{s}{135}[/tex]
Let t be the time when Jeff run one extra lap,
That is
[tex]t\times \frac{s}{135}-t\times \frac{s}{150}=s\\\\t\left ( \frac{1}{135}-\frac{1}{150}\right )=1\\\\t\times \frac{15}{135\times 150}=1\\\\t=1350s[/tex]
So after 1350 seconds Jeff comes side by side to Mandy,
They both start at 8:30 am
1350 s = 22.5 minutes = 22 minutes 30 seconds
Time = 8:52:30 am
