Excluding stoppages, the speed of a train is 45 kmph and including stoppages it is 42 kmph. Of how many minutes does the train stop per hour?	Options
A) 16	B) 4	C) 15	D) 18	E) 12
T = 3/45 * 60= 
<gadget id="calculator">3/45 * 60</gadget>
<output>4</output>
4   Answer: 4
<result>B</result>
Excluding stoppages, the speed of a train is 45 kmph and including stoppages it is 42 kmph. Of how many minutes does the train stop per hour?