the probability that a certain part is defective is 0,10. Assume that the binomial distribution is applicable and that 25 parts are randomly selected from a very large lot. Show all calculations to 3 decimal places.

a. what is the probability that exactly two are defective?

b. what is the brobability that five or more are defective?

c. what is the expected number of defectives in the sample of 25?

Just plug them into the binomial formula.



#1: C(25,2)(\frac{1}{10})^{2}(\frac{9}{10})^{23}

#2: \sum_{5}^{25}C(25,k)(\frac{1}{10})^{k}(\frac{9}{10 })^{25-k}

#3. What is 10% of 25?