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Is it normal to rewear the same two shirts for ten days on a trip

Two works, three is comfortable, four is a habit rather than a need. The thing that makes it work is having something clean to wear while one is drying, so the real number is one on you, one drying, and that's it. If you can only wash every third day because of your schedule, then yes, add a shirt.

58 · in/carry-on ·