Two persons starting from the same place walk at a rate of 5kmph and 5.5kmph respectively. What time will they take to be 8.5km apart, if they walk in the same direction?  Choose the correct choice from the following choices:
A) 18	B) 28	C) 21	D) 17	E) 19
17   17 hrs   The relative speed of the boys = 5.5kmph – 5kmph   = 0.5 kmph   17istance between them is 8.5 km   Time= 8.5km / 0.5 kmph = 17 hrs
<result>D</result>
Two persons starting from the same place walk at a rate of 5kmph and 5.5kmph respectively. What time will they take to be 8.5km apart, if they walk in the same direction?