A boat owner sets off on a river journey. The boat travels 150 km upstream in 12 hours and covers the same distance downstream in 10 hours. On the next day, the boat departs from a point M and follows this pattern: it travels downstream for 4 hours, then upstream for 4 hours. This cycle is repeated for a total of 3 times. After completing these 3 cycles, the boat will be:

The upstream speed is 150 km divided by 12 hours, which is 12.5 km/hr, and the downstream speed is 150 km divided by 10 hours, which is 15 km/hr. In one cycle of 4 hours downstream and 4 hours upstream, the boat covers 60 km downstream and 50 km upstream, netting 10 km downstream from the starting point. Repeating this cycle 3 times means the boat will be 3 times 10 km downstream of point M, resulting in a final position 30 km downstream of point M.

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