999
google search
Google search results:
1: https://www.toppr.com/ask/en-hu/question/a-train-is-running-at-a-speed-of-45-kmhr-and-a-man-is-walking/
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2: https://www.toppr.com/ask/en-us/question/a-man-sitting-in-a-train-travelling-at-the-rate-of-50-kmhr-observes-that/
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3: https://gmatclub.com/forum/time-speed-and-distance-simplified-150163.html
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4: https://www.physicsclassroom.com/reviews/1D-Kinematics/Kinematics-Review-Answers-4
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5: https://www.stocktonusd.net/cms/lib/CA01902791/Centricity/Domain/2213/8th%20Grade%20Science%20Textbook.pdf
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6: https://pa01000192.schoolwires.net/cms/lib/PA01000192/Centricity/Domain/135/Physics/PH%20Ch%203/PH%203.2%20Practice%20Problems0001.pdf
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7: https://tasks.illustrativemathematics.org/content-standards/tasks/193
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8: https://www.exeter.edu/sites/default/files/documents/Math1_2019.pdf
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9: https://www.louisianabelieves.com/docs/default-source/assessment/grade-6-answer-key.pdf?sfvrsn=293b981f_2
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10: https://www.careerbless.com/aptitude/qa/pot1.php
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