Question 1204130
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At 4.45 pm, James, Leo and Noah are at the starting point of a 400-metre circular path. 
James takes 8 minutes to walk 1 round, Leo takes 180 seconds to run I round while Noah cycles 2 rounds in 3 minutes. 
Find the time when all three of them will next meet at the starting point.
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<pre>
James takes 8 minutes to walk 1 round,

Leo takes 3 minutes to run 1 round.


So, if to consider only these two persons, they will be at the starting point simultaneously
next time in  LCM(8,3) = 24 minutes and not earlier.


24 is a multiple of 3, so Noah also will be at the starting point together with James and Leo at this time moment.


So, 24 minutes is the closest time when three friends will meet at the staring point.


The clock will display the time 4.45 pm + 24 minutes = 5.09 pm.    <U>ANSWER</U>
</pre>

Solved.


Thus, I solved the problem mentally without using fractions, working with integer numbers, ONLY.


Compare with the solution by @mananth.