Thanks for the A2A.
First, let's see how many ways there are for 4O, 4A, 1B, and 1AB.
If we use the compound permutation/combination formula, we can do 10!/(4!*4!). We get 6300 ways to sort the 10 people around.
Now let's do \(\frac{{44}^{4}+{42}^4+{10}^{1}+{4}^{1}}{{10}^{10}}\).
Do it on your calculator and you get .0007.
Multiply 6300 and .0007 and you'll get 4.32%
In decimal form, I believe it will be .043.
Cheers!