A decimal operator is if you do something 10 times in a row. For example
1 ++++++++++ 1 = 11
5 ++++++++++ 2 = 25
2 ********** 2 = 2048
You can abbreviate that by multiplying the number of repetitions to the operator:
1 +*10 1 = 11
5 +*10 2 = 25
2 **10 2 = 2048
Because you can leave out the multiplication operator you can write
1 +10 1 = 11
5 +10 2 = 25
2 10 2 = 2048
P.S.: I wrote „operators in decimal“ and I meant o fcourse decimal numbers, because anything else doesn’t make any sense - as I showed.