To minimize working days, we need to maximize holidays. A month can have at most 5 Sundays. It can also have 5 Saturdays in some cases. If a month starts on a Saturday, it will have 5 Saturdays and 5 Sundays if it's a 31-day month with the 31st being a Sunday. However, the question specifies that the second and fourth Saturdays are holidays. In a month with 30 or 31 days, there will always be at least 2 Sundays and at most 5 Sundays. There will also be at least 4 Saturdays and at most 5 Saturdays. The maximum number of holidays occurs when there are 5 Sundays and 5 Saturdays in the month. This would yield 10 holidays. Subtracting these from 30 days gives 20 working days. However, considering typical month structures, a month starting on a Sunday would have 5 Sundays. If it also starts on a Saturday, it would have 5 Saturdays too. The second Saturday would be the 9th, and the fourth would be the 23rd. The Sundays would be 1st, 8th, 15th, 22nd, 29th. This means 5 Sundays and 2 holidays (9th, 23rd) from Saturdays, totaling 7 holidays. This scenario is not ideal for minimum working days. The minimum working days are achieved when there are the maximum number of *designated* holidays. A month can have 4 Sundays and 4 Saturdays, or 5 Sundays and 4 Saturdays, or 4 Sundays and 5 Saturdays. The structure that minimizes working days is when there are 5 Sundays (5 holidays) and the 2nd and 4th Saturdays fall within the month, and we aim for the maximum possible Saturdays that are holidays. If a month has 30 days and starts on a Saturday, the Saturdays are 1st, 8th, 15th, 22nd, 29th. Sundays are 2nd, 9th, 16th, 23rd, 30th. This gives 5 Sundays and 5 Saturdays. Holidays are Sundays (5) + 2nd Sat (8th) + 4th Sat (22nd) = 7 holidays. Working days = 30 - 7 = 23. If a month has 30 days and starts on a Sunday, Sundays are 1st, 8th, 15th, 22nd, 29th (5 Sundays). Saturdays are 7th, 14th, 21st, 28th (4 Saturdays). Holidays are Sundays (5) + 2nd Sat (14th) + 4th Sat (28th) = 7 holidays. Working days = 30 - 7 = 23. If a month has 31 days and starts on a Saturday: Saturdays are 1st, 8th, 15th, 22nd, 29th (5 Saturdays). Sundays are 2nd, 9th, 16th, 23rd, 30th (5 Sundays). Holidays are Sundays (5) + 2nd Sat (8th) + 4th Sat (22nd) = 7 holidays. Working days = 31 - 7 = 24. If a month has 31 days and starts on a Sunday: Sundays are 1st, 8th, 15th, 22nd, 29th (5 Sundays). Saturdays are 6th, 13th, 20th, 27th (4 Saturdays). Holidays are Sundays (5) + 2nd Sat (13th) + 4th Sat (27th) = 7 holidays. Working days = 31 - 7 = 24. Consider a month with 30 days starting on Friday. Saturdays: 2nd, 9th, 16th, 23rd, 30th (5 Saturdays). Sundays: 3rd, 10th, 17th, 24th (4 Sundays). Holidays: Sundays (4) + 2nd Sat (9th) + 4th Sat (23rd) = 6 holidays. Working days = 30 - 6 = 24. Consider a month with 28 days (February in a common year). If it starts on a Saturday: Saturdays are 1st, 8th, 15th, 22nd (4 Saturdays). Sundays are 2nd, 9th, 16th, 23rd (4 Sundays). Holidays: Sundays (4) + 2nd Sat (8th) + 4th Sat (22nd) = 6 holidays. Working days = 28 - 6 = 22. This scenario provides 22 working days, which is the minimum among these common cases. This relies on the specific configuration of days to maximize holidays for a given month length.