We know that speed = distance
/time
==> Distance = speed *
time
==> D = S*T
We
will calculate the time needed foe both John and Jimmy to travel a certain
distance.
Then the distance for both is the same and we
will assume it is D.
Now, we know that Jogns speed = 50
mph
==> S1= 50
mph
==> The time to travel D is
T1
==> D = 50 *
T1............(1)
Now we will determine the equation for
Jimmy.
The speed for Jimmy is S2 = 65
mph
The time needed to travel D is
T2
But we know that Jimmy left 15 minutes later after
John.
==> T2 = T1 - 15
minutes
15 minutes = 0.25
hour
==> T2 = T1 -
0.25
==> D = 65*(T1-
0.25)...........(2)
Now we will solve (1) and
(2).
==> 50*T1 = 65*(T1 -
0.25)
==> 50T1 = 65T1 -
16.25
==> 15*T1 =
16.25
==> T1 = 16.25 / 15
=13/12
13/12 hours = 1 1/12 hours = 1 hour and 5
minutes
Then Jimmy will catch up with John after one hour
and 12 minutes since John left.
John left at
11.
Then 11 + 1:05 =
12:05pm
Then Jimmy will catch up with John at
12:05 pm.
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