It’s easier to work out the probability you *don’t* get it, then subtract that probability from 1.
Probability you don’t get it once:
9/10
Probability you don’t get it the first time or the second time:
9/10 * 9/10 = (9/10)^2
Probability you don’t get it every single time:
(9/10)^5
Probability you do get it at least once:
1 - (9/10)^5
Plug that into a calculator and you get 0.40951, so just over 40% or 4/10.