Math Puzzle: Solve the Subway Conundrum \ stacker news ~science

A young man lives in Manhattan near a subway express station. He is dating two women: one in Brooklyn; one in the Bronx. To visit the woman in Brooklyn he takes a train on the downtown side of the platform; to visit the woman in the Bronx he takes a train on the uptown side of the same platform. Since he likes both women equally well, he simply takes the first train that comes along. In this way, he lets chance determine whether he rides to the Bronx or to Brooklyn. The young man reaches the subway platform at a random moment each Saturday afternoon. Brooklyn and Bronx trains arrive at the station equally often—every 10 minutes. Yet for some obscure reason he finds himself spending most of his time with the woman in Brooklyn: in fact, on the average, he goes there nine times out of 10. Can you decide why the odds so heavily favor Brooklyn?

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I'd suggest you to solve it by yourself before looking at the solution. It's not very hard.

11 sats \ 1 reply \ @SimpleStacker 10 Nov

One possibility is that the train to Brooklyn arrives on the 9th minute, i.e. 10:09, 10:19, 10:29, etc. And the train to the Bronx arrives on the 10th minute, i.e. 10:10, 10:20, 10:30.

So if the man arrives between the 0th to 9th minute of any 10 minute interval, he ends up taking the Brooklyn train, and he only gets on the Bronx train if he arrives between the 9th and 10th minute.

0 sats \ 0 replies \ @IamSINGLE OP 10 Nov

Have you seen the answer? If not now you see it and find if that's correct.