Using a range to sum 2 other ranges

try sumifs

TRIED SUMIF, I CAN'T MAKE IT WORK.

Let me explain a little more. What I am trying to get is an average number of days for each person based on a set up date subtracted from a close date.

So from an excel chart that has multiple people (range1, criteria[persons name]), I ned to subtract the received date (RANGE2) from the closed date (RANGE3) for each project.

So I have:

NAME.....DT RECEIVED.....DT CLOSED
JOE..... 8/10/2017..... 8/20/2017
PETE..... 8/11/2017..... 8/15/2017
JOE..... 8/12/2017..... 8/19/2017

And so on. There are multiple people in this unit and I need to sort based on each person's name, and then have excel perform the subtraction of RANGE2 from RANGE3 for each line with this person's name, and then average the total based on the number of lines. It doesn't seem like it should so hard, but it is totallly escaping me.

Thanks,
Sean