The easiest way to find the female number of any male number is simply to add all it’s digits together.

There are so many ways of doing this and you can never get it wrong.
Let’s start with the smallest male number ten.
10 this number is made from the digits 1 and 0 if you add these together
1+0=1. So the female number of 10 is 1.
The female number of 11 would be 1+1=2 so the female number of 11 is 2.
Here are a few more examples
23 when added we get 5
42 would be 6
62 would be an 8

When adding digits that create another two digit number we add the new digits together. Let’s take 67 as an example
6+7=13 so we continue adding the digits of thirteen
1+3=4 so the female number of 67 is 4.

When the male number has three or more digits there are more ways you can add it all up into a single digit female number.
Let’s take 685 as an example and look at some ways of adding it up.

First we can just add it up
6+8+5=19 then 1+9=10 finally 1+0=1
The female number of 685 is 1.

We could just separate any of it’s digits and start adding from there.
68+5=73 then 7+3=10 and 1+0=1.
We will always get the same answer.

We can even rearrange the digits to create any sum we choose.
58+6=64 then 6+4=10 and 1+0=1
What is important is that all digits are used in making the sum.

Here is another way.
If we take two digits we can add them together into a single digit before adding the last.
685.
6+8=14 then 1+4=5 then 5+5=10 and 1+0=1.
There are so many more combinations that you could do and it really doesn’t matter what route you take you will always get the same answer you simply can’t get it wrong.