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 
.. 
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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