pretty much same as a "standard 10-key.
If you have to add number 1 2 and 3
You enter
1 +
2 +
3 +
=
It's different from the math operation 1 + 3 = 4
it's 1 + 3 + = 4
Similar for substraction
for 4 - 3 + 2 you enter
4+
3-
2+
=
I come here for kudos and IRonMaN's jokes.
