530
google search
Google search results:
1: https://www.quora.com/The-speed-of-a-train-is-12-m-s-and-it-takes-15-seconds-to-cross-a-telegraph-post-What-is-the-length-of-the-train
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2: https://www.toppr.com/ask/question/a-120-metre-long-train-is-running-at-a-speed-of-90-kmhr-it-will/
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3: https://www.toppr.com/ask/en-us/question/a-train-passes-a-telegraph-post-in-8-seconds-and-a-264-m-long-bridge/
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4: https://www.careerbless.com/aptitude/qa/pot1.php
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5: https://gmatclub.com/forum/time-speed-and-distance-simplified-150163.html
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6: https://upscfever.com/upsc-fever/en/test/ssc-cgl/time-distance/chp1.html
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7: https://testbook.com/question-answer/a-train-crosses-a-platform-180-m-long-in-60-sec-at--5ea4320cf60d5d53736fc1c7
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8: https://www.math-only-math.com/train-passes-through-a-bridge.html
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9: https://www.hitbullseye.com/Problems-on-Trains.php
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10: https://www.chegg.com/xml/qandamaster403.xml
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11: https://www.doubtnut.com/pcmb-questions/a-man-is-standing-on-a-railway-bridge-which-is-180-m-long-he-finds-that-a-train-crosses-the-bridge-i-188006
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