Question 396075: Joe and Sam have received walkie-talkies for their birthdays. If they leave from the same point at the same time, Joe walking north at 2.5 mph and Sam walking east at 3 mph, how long will they be able to talk to each other if the range of the walkie-talkies is 4 mi. Round your answer to the nearest minute.
Answer by mananth(16946) (Show Source):
You can put this solution on YOUR website! Joe and Sam have received walkie-talkies for their birthdays. If they leave from the same point at the same time, Joe walking north at 2.5 mph and Sam walking east at 3 mph, how long will they be able to talk to each other if the range of the walkie-talkies is 4 mi. Round your answer to the nearest minute.
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Joe- 2.5 mph
Sam - 3mph
time they walk is the same
let the time be t
2.5t -- joe distance
3t ----- same distance
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they are walking at right angles
use pythagoras theorem
(2.5t)^2 +(3t)^2=4^2
6.25t+9t=16
15.25t=16
t = 16/15.25
time = 1.08 hours
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m.ananth@hotmail.ca
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