<PRE><B>Question 229174</B>
A child traveled 1350 mi by jet and the an additional 135 mi by helicopter.The rate of the jet was 5 times the rate of the helicopter.the entire trip took 4.5 hours.Find the rate of the jet.
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Helicopter DATA:
distance = 135 mi ; rate = x mph ; time = d/r = 135/x hrs
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Jet DATA:
distance = 1350 mi ; rate = 5x ; time = d/r =1350/5x hrs
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Equation:
time + time = 4.5 hrs
135/x + 1350/5x = 4.5
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135/x + 270/x = 4.5
(405/x) = 9/2
Invert both sides to get:
x/405 = 2/9
Multiply both sides by 405 to get:
x = (2/9)*405
x = 90 mph (helicopter rate)
5x = 450 mph (jet rate)
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Cheers,
Stan H.</PRE>