Question 405660
Kathleen and Cade leave simultaneously from the same point hiking in opposite directions, Kathleen walking at 4mph and Cade at 5mph. 
How long can they talk on their walkie-talkies if the walkie-talkies have a 20 mile radius???
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Kathy DATA:
rate = 4 mph ; time = x hrs ; distance = 4x miles
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Cade DATA:
rate = 5 mph ; time = x hrs; distance = 5x miles
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Equation:
dist + dist = 20 miles
4x + 5x = 20
9x  20
x = 2.22 hrs = 2hr 13.2 minutes
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That's how long they can talk.
Cheers,
Stan H.
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