two trains 200 m and 150 m long are running on parallel rails at the rate of 40 kmph and 45 kmph respectively. in how much time will they cross each other, if they are running in the same direction?
Select:
A) 72 sec
B) 132 sec
C) 192 sec
D) 252 sec
E) none
<gadget id="calculator">200 + 150</gadget>
<output>350</output>

<gadget id="calculator">350 / 1_000</gadget>
<output>7/20 = around 0.35</output>

<gadget id="calculator">45 - 40</gadget>
<output>5</output>

<gadget id="calculator">(7/20) / 5</gadget>
<output>7/100 = around 0.07</output>

<gadget id="calculator">3_600 * (7/100)</gadget>
<output>252</output>

<result>D</result>
two trains 200 m and 150 m long are running on parallel rails at the rate of 40 kmph and 45 kmph respectively. in how much time will they cross each other, if they are running in the same direction?
multiply(const_3600, divide(divide(add(200, 150), const_1000), subtract(45, 40)))
solution relative speed = ( 45 - 40 ) kmph = 5 kmph = ( 5 x 5 / 18 ) m / sec = ( 25 / 18 ) m / sec time taken = ( 350 x 18 / 25 ) sec = 252 sec . answer d