Q:

5.28 A manufacturer knows that on average 20% of the electric toasters produced require repairs within 1 year after they are sold. When 20 toasters are randomly selected, find appropriate numbers x and y such that (a) the probability that at least x of them will require repairs is less than 0.5; (b) the probability that at least y of thE?

Accepted Solution

A:
Answer:A) probability that at least x of them will require repairs is less than 0.5 is 4Step-by-step explanation:sample size, n = 20p = success probability of toaster = 0.2q = failure probability of toaster =1- p = 1- 0.2 =0.8mean, , μ = n * p = 20 * 0.2 = 4standard deviation, [tex]\sigma = \sqrt{npq} = \sqrt{(20 * 0.2 *0.8)} = 1.79[/tex]a) the probability that at least some of them require repairs < 0.5.for [tex]p \geq 0.5[/tex] value of z = 0 we know [tex]z  =\frac{x -\mu}{\sigma}[/tex][tex]0 = \frac{X -4}{1.79}[/tex] from z tableX =  4B)  SECOND PART IS INCOMPLETE { DATA IS INCOMPLETE}