Without any stoppage, a person travels a certain distance at an average speed of 42 km/h, and with stoppages he covers the same distance at an average speed of 28 km/h. How many minutes per hour does he stop? Choose one.
A) 26 minutes  B) 20 minutes  C) 17 minutes  D) 16 minutes  E) 18 minutes
Explanation:   Let the total distance to be covered is 84 kms.   Time taken to cover the distance without stoppage = 84/42= 
<gadget id="calculator">84/42</gadget>
<output>2</output>
2 hrs   Time taken to cover the distance with stoppage= 84/28= 
<gadget id="calculator">84/28</gadget>
<output>3</output>
3 hrs.   Thus, he takes 60 minutes to cover the same distance with stoppage.   Therefore, in 1 hour he stops for 20 minutes.   Answer: 20 minutes
<result>B</result>
Without any stoppage, a person travels a certain distance at an average speed of 42 km/h, and with stoppages he covers the same distance at an average speed of 28 km/h. How many minutes per hour does he stop?