Question

In a bowl of jelly beans there are 12 red, 10 black, 5 white, and 3 green. If three jellly beans are chosen one at a time, what is the probability that 3 black jelly beans will be chosen? WILL MEDAL

Answer 1

\[
\frac{10}{12+10+5+3}\cdot
\frac{9}{12+9+5+3}\cdot
\frac{8}{12+8+5+3}
\]

Answer 2

This is sampling without replacement:
\[\large P(3\ black)=\frac{10C3}{30C3}=\frac{10\times9\times8}{30\times29\times28}=you\ can\ calculate\]

Answer 3

\[
^{10}P_3 = \frac{10!}{(10-3)!} = 10\times 9\times 8
\]