If I have to allocate 130 days (work schedule Jan-June weekdays) in
the following manner why doesn't the total come out to 130 days? 2
people work 40% (52 days); 2 work 20%(26 days). 52 + 52+26+26+=156? (I
was never good at math, after open-heart surgery--and when tired my
brain does not work properly)

Maybe I'm misunderstanding something, but consider your math this way:

40% + 40% + 20% + 20% = 120%.

If only one person worked 20%, you'd have 100%, which would be 130.

Does that make any sense? My brain isn't working too well tonight, either. ;-)

That was a very tactful way of suggesting the correct answer, Pink  -
or was your mind really not working too well?  ;)

Maybe the persons don't work full time  - or not all of them -  so
that two or more are working on some of the 130 days.

Pinkfreud is exceedingly gracious...  Myoarin is
insightful/inciteful... We had a thunderstorm Saturday night when I
was working on this and rain gives me migraines.  (I am a mess...but
manage to work 50 hours a week for a genius.)  Typically, I do not
second-guess him.  He said give 40% to A, 40% to B, and 20% to me and
C.  I heard 20% each for the last two doctors and kept trying to make
120 come out to 100%.  Numbers have never been my forte.  (I can
design a dress, make the pattern and sew it up, but cannot add 2 + 2
under certain conditions...)

Again, thank you for the thoughtful replies.

From your description, it sounds to me as if the 20% is meant to be
split between the last two people, rather than having 20% allocated to
each person.

I was going on the basis that there had to be four people and thinking (?)
Pink might have meant "If only one person worked 40% ..."

Anyway, I have a great respect for people who can make dress patterns.
My mother  - bless her soul -  could, once a strapless dress for my
sister from a small photo.  When it was successfully finished, she
inadvertantly caused great amusement with the comment:  "You know,
with a strapless dress, there are a couple of difficult points."

I hope the weather has improved.
Cheers, Myoarin