Question 341350
Joe drove 210 km at 70 km/h and then another 210 km at 105 hm/h. It took Bill the same length of time to drive the entire 420 km at constant speed. What was Bill's speed?
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{{{ time = distance / speed}}}
Time taken by Joe = {{{ (210/70) + (210/105)}}}
Time taken = 3 + 2 = 5 hours.
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Bill takes same time to go 420 kms .
Bill's speed = 420/5 = 84 km/h