<PRE><B>Question 783894</B>
bus a takes 21 minutes to complete its route. bus b takes 35 minutes to complete its route. at what time will they arrive at the bus station at the same time? 
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Find the least common multiple of 21 and 35:
Prime Factor form:
21 = 3*7
35 = 5*7
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least common multiple = 3*5*7 = 105
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Answer:: 105 minutes
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Cheers,
Stan H.
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