Weighted average with dynamic total based on filter

Anonymous , Create a date table with week columns

Have these new columns in Date Table, Week Rank is Important in Date/Week Table
Week Start date = 'Date'[Date]+-1*WEEKDAY('Date'[Date],2)+1
Week End date = 'Date'[Date]+ 7-1*WEEKDAY('Date'[Date],2)
Week Rank = RANKX(all('Date'),'Date'[Week Start date],,ASC,Dense)
OR
Week Rank RANKX(all('Date'),'Date'[Year Week],,ASC,Dense) //YYYYWW format
WeekDay = weekday([Date])

These measures can help
This Week = CALCULATE(sum('Table'[Qty]), FILTER(ALL('Date'),'Date'[Week Rank]=max('Date'[Week Rank])))
Last Week = CALCULATE(sum('Table'[Qty]), FILTER(ALL('Date'),'Date'[Week Rank]=max('Date'[Week Rank])-1))

Avg of Week  =CALCULATE(Averagex(Values(Date[Date]),CALCULATE(sum('Table'[Qty]))) , FILTER(ALL('Date'),'Date'[Week Rank]=max('Date'[Week Rank])))

Time Intelligence, DATESMTD, DATESQTD, DATESYTD, Week On Week, Week Till Date, Custom Period on Period,
Custom Period till date: https://youtu.be/aU2aKbnHuWs&t=145s