Probability change

Suppose i have a set [A,B,C]
Probability of A =10% B=40% C=50%
If probability of C lowers to 25%, how the remainder value is distributed(proportionaly)?
I know it suppose to get like 15(+50%),60(+50%),25 but what if the set grows?
exmaple       5,77,3,15(-5) becomes 6.65,102,4,10
I'm looking for a formula for arbitrary sets of probability(not just 3).

You have a set X.
Do whatever you like to the set.
Once you're done scale the set such that the sum of all elements = 1 == 100%.
scaled X = (1 / sum(X))

Also do your own homework or you'll never learn