It takes Riaz 30 minutes to mark a paper, Razi only takes 25 minutes to mark a paper, if

they both start marking a paper at 11:00 AM, what is the first time they will finish marking
a paper at same time?

1 answer

The LCM(25,30)=5*LCM(5,6)=150
So, after 150 minutes they will both have finished sets of papers.
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