What is the probability that the first $2$ balls you pick are white, and the last $3$ are black? Write your answer as

ans $=$

In $[]$:

# your code here

fail$()$ # No Answer $-$ remove if you provide an answer

In $[]$: # Check whether $6$ th and $7$th decimal digits are $8$ and $0,$ respectively

if $($test$\_$that $($desc$="\text{'}",$ code

expect$\_$equal$(($floor$($ans$*10^7)\%100==80),$ TRUE$)$

$\})!=$ TRUE$)$ stop$("$Sorry$,$ your variable ans is incorrect."$)$

In $[]$: # Check whether the answer is correct $($hidden test$)$