If 30 transformers are picked at random, what is the probability that all 30 are nondefective?

Defective Transformers In a shipment of 50 transformers, 10 are known to be defective. If 30 transformers are picked at random, what is the probability that all 30 are nondefective? Assume that all transformers look alike and have an equal probability of being chosen. Round your answer to 6 decimal places.|||This is statistics. I will use the Bernoulli trial:





What you are doing is 30 combination 30 as in: 30C30





Next find the p(defective) That is 10/50 which if i am correct, is 0.2





That means p(okay) is 0.8.





The equation would be:





30C30 (0.2)^0 (0.8)^30





Answer is: .00123794





You round it.|||Why don't you do your own homework?|||You have to know whether the sampling is with or without replacement.


With replacement the answere is just .8^30 = 0.00123794





Without replacement which makes more sense is 40/50 * 39/49 * 38/48 *...* 11/21





= 40! * 20! / ( 50! * 10!) = 0.000017986