Question

Of 6 seniors and 7 juniors, 5 will be selected for a scholarship. What is the probability that exactly 3 of 5 students selected will be seniors?

Answer 1

@satellite73 @ganeshie8 @AccessDenied

Answer 2

@mathmale

Answer 3

\[P(3\ out\ of\ 5\ be\ seniors)=\frac{6C3\times7C2}{13C5}=you\ can\ calculate\]

Answer 4

oh this makes sense! because if 3 are seniors 2 must be juniors! thank you so much!

Answer 5

what equation is this by the way?

Answer 6

You're welcome :)

Answer 7

The equation is for the hypergeometric distribution.

Answer 8

The hypergeometric distribution is generated when a sample of size n is taken (without replacement) from a population containing a items of one particular type, and b of another type. The probability that the sample contains exactly x of the particular type is given by:
\[P(x)=\frac{{a \choose x} {b \choose n-x}}{{a+b \choose n}}\]