ramu rides his bike at an average speed of 45 km / hr and reaches his desitination in 4 hours. somu covers the same distance in 6 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 option:
A) 23 minutes
B) 30 minutes
C) 43 minutes
D) 23 minutes
E) 33 minutes
<gadget id="calculator">45 * 4</gadget>
<output>180</output>

<gadget id="calculator">45 - 9</gadget>
<output>36</output>

<gadget id="calculator">180 / 36</gadget>
<output>5</output>

<gadget id="calculator">180 / 6</gadget>
<output>30</output>

<gadget id="calculator">30 + 10</gadget>
<output>40</output>

<gadget id="calculator">180 / 40</gadget>
<output>9/2 = around 4.5</output>

<gadget id="calculator">5 - (9/2)</gadget>
<output>1/2 = around 0.5</output>

<gadget id="calculator">(1/2) * 60</gadget>
<output>30</output>

<result>B</result>
ramu rides his bike at an average speed of 45 km / hr and reaches his desitination in 4 hours. somu covers the same distance in 6 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 ).
multiply(subtract(divide(multiply(45, 4), subtract(45, 9)), divide(multiply(45, 4), add(divide(multiply(45, 4), 6), 10))), const_60)
distance travelled by ramu = 45 * 4 = 180 km somu travelled the same distance in 6 hours . his speed = 180 / 6 = 30 km / hr hence in the conditional case , ramu ' s speed = 45 - 9 = 36 km / hr and somu ' s speed = 30 + 10 = 40 km / 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 : b