You can
put this solution on YOUR website!distance(d)=rate(r) times time(t) or d=rt;r=d/t and t=d/r
Let t=time it takes Jan to run around the entire track
And let L=length of the track
We are told that Maria can run around the track in 40 sec.
So we know that Maria's rate is d/t=L/40
The distance Maria travels in 15 sec =rt=(L/40)*15 or 15L/40 or 3L/8 ft
Together, Jan and Maria can run around the length of the track (L) in 15 sec. So the distance Jan travels in 15 sec=L-distance Maria travels in 15 sec, or
The distance Jan travels in 15 sec =L-3L/8=5L/8 ft
Now we can set up a simple ratio to get to the answer
5L/8 is to 15 sec as L is to t or
(5L/8)/15=L/t simplifying the left side we get
L/24=L/t multiply both sides by 24t
Lt=24L divide both sides by L
t=24 sec--------------------time it takes Jan to run around the track
Ck
Jan's rate is L/24
In 15 sec, Jan runs (L/24)*15 or 15L/24 ft
Maria's rate is L/40
In 15 sec, Maria runs (L/40)*15=15L/40
15L/24+15L/40=L
3L/8+5L/8=8L/8=L
L=L
Hope this helps---ptaylor
