two boys starts from the same place walking at the rate of 5 kmph and 5.5 kmph respectively in the same direction. what time will they take to be 8.5 km apart?  Select the correct option:
A) 17 hr	B) 14 hr	C) 12 hr	D) 19 hr	E) 23 hr
<gadget id="calculator">5.5 - 5</gadget>
<output>0.5</output>

<gadget id="calculator">8.5 / 0.5</gadget>
<output>17</output>

<result>A</result>
two boys starts from the same place walking at the rate of 5 kmph and 5.5 kmph respectively in the same direction. what time will they take to be 8.5 km apart?
divide(8.5, subtract(5.5, 5))
"relative speed = 5.5 - 5 = 0.5 kmph ( because they walk in the same direction ) distance = 8.5 km time = distance / speed = 8.5 / 0.5 = 17 hr answer is a"