(New page: By definition W is a binomial random variable so it's distribution (PMF) can be represented by: P(W = m) = (n-k) ( m ) where m is the number of questions missed. P(W = m) = ...) |
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P(W = m) = (n-k) | P(W = m) = (n-k) | ||
| − | + | m where m is the number of questions missed. | |
P(W = m) = (4/5)^m *(1 - 4/5)^(n-k-m) | P(W = m) = (4/5)^m *(1 - 4/5)^(n-k-m) | ||
| Line 10: | Line 10: | ||
P(C) = k + (n-k) (1/5)^r * (1 - 1/5)^(n-k-r) | P(C) = k + (n-k) (1/5)^r * (1 - 1/5)^(n-k-r) | ||
| − | + | r | |
Revision as of 15:24, 23 September 2008
By definition W is a binomial random variable so it's distribution (PMF) can be represented by:
P(W = m) = (n-k)
m where m is the number of questions missed.
P(W = m) = (4/5)^m *(1 - 4/5)^(n-k-m)
B) C = n - W
P(C) = k + (n-k) (1/5)^r * (1 - 1/5)^(n-k-r)
r
