I have a set of a set of data that I am trying to do a SUMIF formula on and am having difficulty finding the correct formula, Essentially I have 3 columns. 

Project Quarter


Sample Size

I am trying to sumif the Sample Size column range if the criterian is met for a specific project


Is it possible to get a date (mm/dd/yy) from a week number?  Ultimately I'd like to get the Friday of the week number.

Using today as an example (1/11/18), the week number is 2 and  Friday is 1/12/18.  I've tried some different Excel formulas but am not getting anything to work in Smartsheet.