SOLUTION: Two brothers leave from the same point driving in opposite directions, the first brother driving at 60 miles per hour and the second driving at 45 mph. The first brother has a one

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Question 675221: Two brothers leave from the same point driving in opposite directions, the first brother driving at 60 miles per hour and the second driving at 45 mph. The first brother has a one hour head start. How long will they be able to talk on their car phones if the phones have a 260 mile-range?
Found 2 solutions by stanbon, josmiceli:
Answer by stanbon(75887) About Me  (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 60 miles per hour and the second driving at 45 mph. The first brother has a one hour head start. How long will they be able to talk on their car phones if the phones have a 260 mile-range?
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1st brother DATA:
rate = 60 mph ; time = x+1 hrs ; distance = rt = 60x+60 miles
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2nd brother DATA:
rate = 45 mph ; time = x hrs ; distance = rt = 45x miles
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Equation:
distance + distance = 260 miles
60x+60 + 45x = 260
105x = 200
x = 40/21 = 1.904 hrs = 1 hr 54 minutes 17 seconds
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Cheers,
Stan H.

Answer by josmiceli(19441) About Me  (Show Source):
You can put this solution on YOUR website!
The 1st brother's head start is +60%2A1+=+60+ mi
You can start a stop watch when the 2nd brother leaves
Let +d+ = the distance the 1st brother will now travel
+200+-+d+ = the distance the 2nd brother will now travel
Let +t+ = the time it takes for them to be +260+-+60+=+200+
miles apart.
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1st brother's equation:
(1) +d+=+60t+
2nd brother's equation:
(2) +200+-+d+=+45t+
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Substitute (1) into (2)
(2) +200+-+60t+=+45t+
(2) +105t+=+200+
(2) +t+=+1.9048+ hrs
+.9048%2A60+=+54.3+
They will be able to talk for 1 + 1 + 54 min
or 2 hours and 54 minutes