two trains 160 m and 160 m long run at the speed of 60 km / hr and 40 km / hr respectively in opposite directions on parallel tracks. the time which they take to cross each other is?
Pick:
A) 10.52 sec B) 18.8 sec C) 14.52 sec D) 10.8 sec E) 11.52 sec
<gadget id="calculator">160 + 160</gadget>
<output>320</output>

<gadget id="calculator">60 + 40</gadget>
<output>100</output>

<gadget id="calculator">10 / 36</gadget>
<output>5/18 = around 0.277778</output>

<gadget id="calculator">100 * (5/18)</gadget>
<output>250/9 = around 27.777778</output>

<gadget id="calculator">320 / (250/9)</gadget>
<output>288/25 = around 11.52</output>

<result>E</result>
two trains 160 m and 160 m long run at the speed of 60 km / hr and 40 km / hr respectively in opposite directions on parallel tracks. the time which they take to cross each other is?
divide(add(160, 160), multiply(add(60, 40), const_0_2778))
"relative speed = 60 + 40 = 100 km / hr . = 100 * 5 / 18 = 250 / 9 m / sec . distance covered in crossing each other = 160 + 160 = 320 m . required time = 320 * 9 / 250 = 288 / 25 = 11.52 sec . answer : e"