Incorrect Total showing on the Table

rsacherry1025 

The problem you are running into is from what is returned by SELECTEDVALUE(Table1[Convert_StartDate]) on the total row, there it returns a BLANK() so you need to adjust the measure a bit.

We can create a table in the measure to apply as a filter, something like this.

Effort Hours = 
CALCULATE (
    DIVIDE ( SUM ( Table3[Duration] ), 60 ),
    FILTER (
        ADDCOLUMNS (
            SUMMARIZE ( Table3, Table3[Ticket] ),
            "@Start", CALCULATE ( MAX ( Table1[Convert_StartDate] ) ),
            "@Created", CALCULATE ( MAX ( Table2[Convert_CreatedOn] ) )
        ),
        [@Created] >= [@Start]
    )
)

That gives me the correct total based on your sample although it may need some tweeking depeding on how your model is layed out.