When circuit boards used in the manufacture of compact disc players are tested, the long-run percentage of defectives is 5%. Let X = the number of defective boards in a random sample of size n = 20, so X ~ Bin(20, 0.05). (Round your probabilities to three decimal places.)
(a) Determine P(X ? 2).
(b) Determine P(X ? 5).
(c) Determine P(1 ? X ? 4).
(d) What is the probability that none of the 20 boards is defective?
expected value _______ boards
standard deviation _______ boards
You may need to use the appropriate table in the Appendix of Tables to answer this question.