15 weeks is 105 days, no matter what year it is.
A leap year has 52 weeks and 2 days.
1 year = 52 1/7 weeks (not counting leap years) 21 years = 1095 weeks (with some days left over if you are counting leap years) ■
In a regular year there are 365 days, so that is 52 weeks and 1 day. In a leap year there are 366 days, so that is 52 weeks and 2 days.
52 weeks and 2 days. Non-leap years have 365 days, 1 day more than 52 weeks of 7 days each. Leap years have 366 days.
17 weeks and 1 day in a normal year and 17 weeks and 2 days in a leap year.17 weeks and 1 day in a normal year and 17 weeks and 2 days in a leap year.17 weeks and 1 day in a normal year and 17 weeks and 2 days in a leap year.17 weeks and 1 day in a normal year and 17 weeks and 2 days in a leap year.17 weeks and 1 day in a normal year and 17 weeks and 2 days in a leap year.17 weeks and 1 day in a normal year and 17 weeks and 2 days in a leap year.17 weeks and 1 day in a normal year and 17 weeks and 2 days in a leap year.17 weeks and 1 day in a normal year and 17 weeks and 2 days in a leap year.17 weeks and 1 day in a normal year and 17 weeks and 2 days in a leap year.17 weeks and 1 day in a normal year and 17 weeks and 2 days in a leap year.17 weeks and 1 day in a normal year and 17 weeks and 2 days in a leap year.
A normal year has 365 days. A leap year has 366. A normal year has 52 weeks and 1 day, a leap year has 52 weeks and 2 days.
Making the assumption that one of those four years is a leap year, 4 years and 15 weeks is equal to (3 x 365) + 366 + (15 x 7) = 1566 days.
There are about 208 weeks in 4 years including a leap year but each year has an extra day but a leap year would have two extra days (208 weeks + 6 days about).
379 days if it is a normal year and 2 weeks, or 380 days if it is a leap year and 2 weeks.
52 and 1/7 weeks
6 leap years = 6*366 = 2196 days = 313 weeks + 5 days
63 days is equal to 9 weeks.