Question 1019821
When we start, there are 4 blue of 9 total.
The chance for the first one to be blue is 4/9
After that, we have 3 blue and 8 total
so the chance for the second blue is 3/8
then, to choose one of the 3 whites of the remaining 7 has a chance of 3/7
As these things have to happen in succession, we will multiply the probabilities and get

<a href="http://www.tiger-algebra.com/drill/(4/9)$(3/8)$(3/7)/">(4/9)*(3/8)*(3/7)</a>