Question 325191
 The Griswold's averaged 45 mph on their way to Las Vegas and 60 mph on the way back home using the same route. Find the distance from their home to Las VEgas if the total driving time was 70 hours.
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To Las Vegas DATA:
rate = 45 mph ; distance = x miles ; time = x/45 hrs.
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From Las Vegas DATA:
rate = 60 mph ; distance = x miles ; time = x/60 hrs.
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Equation:
time + time = 70 hrs.
x/45 + x/60 = 70
Multiply each term by (45*60) to get:
60x + 45x = 70*60*45
105x = 70*60*45
x = 1800 miles
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cheers,
Stan H.
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