Question

of one hundred and forty two students attending college , 23 are criminal justice majors. if 9 are selected at random, determine the probability each 9 criminal justice major. set up the problem as if it were to be solved but don't solve.

Answer 1

The probablity that first one selected is a criminal justice major is,

`P_1=(23)/(142)`

Now, the probablity that second one is a criminal justice major is when selected without replacement,

`P_2=(22)/(141)`

Simirally,

`\begin{gathered} P_3=(21)/(140) \\ P_4=(20)/(139) \\ \ldots.\text{.} \end{gathered}`

Thus, using the multiplication theorem,

`\begin{gathered} P=P_1* P_2*\ldots\ldots.P_9 \\ =(23)/(142)*(22)/(141)*(21)/(140)*\ldots\ldots\ldots\ldots\ldots(15)/(134) \end{gathered}`

Thus, the above equation gives the requried probablity.