At 10Am adam started out at 60 kilometers per hour to catch

At 10Am, adam started out at 60 kilometers per hour to catch tom , who had a three hour head start. If adam was still 70 kilometers behind at 6 pm, how fast was tom driving?

Solution

Adam DATA:
rate= 60 km/hr ; time = 8 hr. ; distance = tr= 480 km
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Tom DATA:
time=8+3 = 11 hr;
Let Tom\'s rate be x km/hr
In 3 hrs he goes 3x km
He then covers the 480 km that Adam covers later
He then is 70 km ahead of Adam
Tom\'s distance = 3x+480+70=3x+550 km
Tom\'s distance is also 11x because he was on the road for 11 hours
EQUATION:
3x+550=11x
8x=550
x=68.75 km/hr (This is Tom\'s rate)
Cheers,
Stan H.
rate=d/t=550/11=50 km/hr
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Tom\'s rate is 50 km/hr.