Step-by-step explanation:
the info about renting skis is only there to confuse us and has no impact on the solution.
how many days ?
we find the answer by seeing how often the price of a daily pass fits into the season pass :
350 / 63 = 5.55555555...
so, we see, 5 daily passes are still cheaper than the season pass.
but when buying 6 daily passes, then they are more eclectic than the season pass.
so, he has to ski for at least 6 days to make the season pass less expensive than daily passes.