Question

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?

Answer 1

Answer:

A) probability that at least x of them will require repairs is less than 0.5 is 4

Step-by-step explanation:

sample size, n = 20

p = success probability of toaster = 0.2

q = failure probability of toaster =1- p = 1- 0.2 =0.8

mean, , μ = n * p = 20 * 0.2 = 4

standard deviation, $\sigma = \sqrt{npq} = \sqrt{(20 * 0.2 *0.8)} = 1.79$

a) the probability that at least some of them require repairs < 0.5.

for $p \geq 0.5$ value of z = 0

we know $z =\frac{x -\mu}{\sigma}$

$0 = \frac{X -4}{1.79}$ from z table

X =  4

B)  SECOND PART IS INCOMPLETE { DATA IS INCOMPLETE}