"Av days of receivable" and "weighted av. collection period"

I am getting confused btwn “Av days of receivable” and “weighted av. collection period”. Can sm1 help plz. Whats the difference btwn two? Thnx

is it possible that these are similar concepts from different sources in the curriciulum? I guess the first one is calculated from accounting data in the “fsa” section, and the second from internal data in the “corporate finance” section? true?