Question 1144555
Two cyclists are racing around a circular track. Jody can ride once around the track in 6 minutes. Joni takes 4 minutes.
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Hint:  Assuming they start at the same place at the same time, it's the LCM, the Least Common Multiple of 6 and 4 minutes.
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To Ikelyn: 
The faster "laps" the slower.
To "lap" someone is to pass them while going around a repetitive course.
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It's sort of idiomatic.  Not obvious to people to whom English is not their 1st language.