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# A and B walking around a circular park at a speed of 2 rounds per hour and 3 rounds per hour respectively. If they start at 8 a.m. from the same point in opposite directions, then how many times shall they meet each other before 9.30 a.m.?

[ A ]    5
[ B ]    6
[ C ]    7
[ D ]    8
 Answer : Option C Explanation : Relative speed = Speed of A + Speed of B (they walk in opposite directions) = 2 + 3 = 5 rounds per hour They cross each other 5 times in 1 hr and 2 times in $1^ 2$ hr Time duration from 8 am to 9.30 am = 1.5 hour Hence they cross each other 7 times before 9.30 am