This is a variable number. You need to state a start and/or end date or time.
Exactly 11 weeks after December 20, 2011 is March 6, 2012.
In any given year, adding 11 weeks to March 23, gives June 8.
The 14th of January 2013.
March 3 2011 is the date 11 weeks before May 19 2011.
Today is Monday, May 19, 2014. If you subtract 27 weeks from today's date, or 189 days, the date would be Monday, November 11, 2013.
September 14 2012 + 11*7 days = 30 November 2012.
As of today, the desi date in Pakistan is 3rd Safar 1445 AH according to the Islamic lunar calendar. The Islamic calendar is about 11 days shorter than the Gregorian calendar, so the corresponding Gregorian date will vary each year. The current month, Safar, is the second month in the Islamic calendar.
To calculate the date 11 weeks ago, you would go back 77 days from today. Assuming today is October 3, 2023, 11 weeks ago would be July 18, 2023.
49 weeks ago was approximately 11 months and 3 weeks ago from today.
Today is Sunday 4 April 2010. 75 weeks from now, the date will be Sunday 11 September 2011.
As today is January 11, the date 28 weeks and 6 days ago would have been June 23.
To determine the date that was 42 weeks ago, you can subtract 42 weeks from today's date. Since there are 7 days in a week, 42 weeks equals 294 days. If today is October 2, 2023, then 294 days ago was December 11, 2022.