Probability help

[Relaxo]

I need some help figuring out a probability...

Let's say I have a 1d20 roll, +4dF, but on the Fudge dice, only count any + that come up. So that's Four 1 in 3 chances of getting +1. ... what does that work out to, compared to 1d20?
(I'm guessing four 1 in 3's is approximately +1.3, on average, right? ish?)

the concept is to use 4dF for "luck" or "fortune" (and - only for "cursed" or whatnot)... but I"m not sure if it's worth the bother or if (dis)Advantage from 5e is just easier and better.
(If I'm not mistaken, advantage works out to about +3)

THANKS!!!

[Arduin]

(If I'm not mistaken, advantage works out to about +3)

THANKS!!!

Advantage averages out to ~±5!

[alcyone]

For any nontrivial dice probability stuff I usually go to anydice.com . It's pretty powerful; you can create custom dice with arbitrary sequences in them.

[Relaxo]

@ Arduin... see? I need all the help i can get.

Thanks Aergraith!