Ramu rides his bike at an average speed of 45 km/hr and reaches his desitination in four hours. Somu covers the same distance in six hours. If Ramu covered his journey at an average speed which was 9 km/hr less and Somu covered his journey at an average speed which was 10 km/hr more, then the difference in their times taken to reach the destination would be (in minutes)?  Choose the correct choice from the following
A) 11	B) 30	C) 88	D) 66	E) 41
Distance travelled by Ramu = 45 * 4= 
<gadget id="calculator">45 * 4</gadget>
<output>180</output>
180 km   Somu travelled the same distance in 6 hours.   His speed= 180/6= 
<gadget id="calculator">180/6</gadget>
<output>30</output>
30 km/hr   Hence in the conditional case, Ramu's speed= 45 - 9= 
<gadget id="calculator">45 - 9</gadget>
<output>36</output>
36 km/hr and Somu's speed= 30 + 10= 
<gadget id="calculator">30 + 10</gadget>
<output>40</output>
40km/hr.   Therefore travel time of Ramu and Somu would be 5 hours and 4.5 hours respectively. Hence difference in the time taken= 0.5 hours = 30 minutes.   Answer:30
<result>B</result>
Ramu rides his bike at an average speed of 45 km/hr and reaches his desitination in four hours. Somu covers the same distance in six hours. If Ramu covered his journey at an average speed which was 9 km/hr less and Somu covered his journey at an average speed which was 10 km/hr more, then the difference in their times taken to reach the destination would be (in minutes)?