excluding stoppages, the average speed of a bus is 120 km / hr and including stoppages, the average speed of the bus is 40 km / hr. for how many minutes does the bus stop per hour?	Select the correct option
A) 15 min  B) 18 min  C) 16 min  D) 20 min  E) 40 min
<gadget id="calculator">1 * 60</gadget>
<output>60</output>

<gadget id="calculator">40 / 120</gadget>
<output>1/3 = around 0.333333</output>

<gadget id="calculator">(1/3) * 60</gadget>
<output>20</output>

<gadget id="calculator">60 - 20</gadget>
<output>40</output>

<result>E</result>
excluding stoppages, the average speed of a bus is 120 km / hr and including stoppages, the average speed of the bus is 40 km / hr. for how many minutes does the bus stop per hour?
subtract(multiply(const_1, const_60), multiply(divide(40, 120), const_60))
"in 1 hr , the bus covers 120 km without stoppages and 40 km with stoppages . stoppage time = time take to travel ( 120 - 40 ) km i . e 80 km at 120 km / hr . stoppage time = 80 / 120 hrs = 40 min answer : e"