<PRE><B>Question 151115</B>
Two private planes, owned by engr,roel , leave a common airport at the same time and travel in opposite direction. If one travels at 75 kph(kilometer per hour) and the other at 90 kph, how long will it take them to be 800km apart?
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1st Plane DATA:
 rate = 75 kph ; time = x hrs ; distance = 75x km
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2nd Plane DATA:
 rate = 90 kph ; time = x hrs ; distance = 80x km
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EQUATION:
distance One + distance two = 800 km
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75x + 80x = 800
155x = 800
x = 5.1613 hrs
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Cheers,
Stan H.</PRE>