A train ,140 meters long travels at a speed of 45 km/hr crosses a bridge in 30 seconds. The length of the bridge is Choose the correct choice:
A) 270 m  B) 245 m  C) 235 m  D) 220 m  E) 240 m
Explanation:   Assume the length of the bridge = x meter   Total distance covered = 140+x meter   total time taken = 30s   speed = Total distance covered /total time taken = (140+x)/30 m/s   =&gt; 45 Ã— (10/36) = (140+x)/30   =&gt; 45 Ã— 10 Ã— 30 /36 = 140+x   =&gt; 45 Ã— 10 Ã— 10 / 12 = 140+x   =&gt; 15 Ã— 10 Ã— 10 / 4 = 140+x   =&gt; 15 Ã— 25 = 140+x = 375   =&gt; x = 375-140= 
<gadget id="calculator">375-140</gadget>
<output>235</output>
235   Answer: Option 235 m
<result>C</result>
A train ,140 meters long travels at a speed of 45 km/hr crosses a bridge in 30 seconds. The length of the bridge is