Question 1055676: Two brothers leave from the same point driving in opposite directions, the first brother driving at 45 miles per hour and the second at 60 mph. The first brother has a one-hour head start. If each brother has a communication device that allows him to talk to the other for up to a 200-mile range, how long will they be able to talk to each other?
Found 2 solutions by josgarithmetic, MathTherapy:
Answer by josgarithmetic(39616)   (Show Source):
You can put this solution on YOUR website!
SPEED TIME DISTANCE
POS 45 t+1
NEG 60 t
TOTAL 200
SPEED TIME DISTANCE
POS 45 t+1 45(t+1)
NEG 60 t 60t
TOTAL 200
You are looking for t+1.
Answer by MathTherapy(10551)  (Show Source):
You can put this solution on YOUR website!
Two brothers leave from the same point driving in opposite directions, the first brother driving at 45 miles per hour and the second at 60 mph. The first brother has a one-hour head start. If each brother has a communication device that allows him to talk to the other for up to a 200-mile range, how long will they be able to talk to each other?
From the time the slower brother started travelling to the time both are 200 miles apart, they will be able to communicate
Therefore, let time 1st (slower) brother took to get 200 miles from 2nd brother be T
Then time 2nd (faster) brother took to get 200 miles from 1st brother is: T - 1
When they’re 200 miles apart, the slower and faster brothers would’ve traveled 45T and 60(T – 1), or 60T – 60 miles, respectively
We then get: 45T + 60T – 60 = 200
105T = 260
T, or time both can communicate =  , or 
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