Two persons starting from the same place walk at a rate of 10kmph and 14.5kmph respectively. What time will they take to be 18km apart, if they walk in the same direction?  Choose the correct choice from the following:
A) 4 hrs
B) 9 hrs
C) 5 hrs
D) 2 hrs
E) 6 hrs
The relative speed of the boys = 14.5kmph – 10kmph   = 4.5 kmph   Distance between them is 18 km   Time= 18km / 4.5 kmph = 4 hrs   4 hrsnswer : 4 hrs
<result>A</result>
Two persons starting from the same place walk at a rate of 10kmph and 14.5kmph respectively. What time will they take to be 18km apart, if they walk in the same direction?