Question

In: Statistics and Probability

a) (i). A manufacturer of metal pistons finds that on the average, 12% of his pistons...

a) (i). A manufacturer of metal pistons finds that on the average, 12% of his pistons are

rejected because they are either oversize or undersize. What is the probability that a

batch of 10 pistons will have not more than 2 rejections?

(ii). A company makes electric motors. The probability an electric motor is defective

is 0.01. What is the probability that a sample of 300 electric motors will contain

exactly 5 defective motors?

Q4(b) (i). The time in hours, during which an electrical generator is operational is a random

variable that follows an exponential distribution with mean 180. What is the

probability that a generator of this type will be operational for

(i) Less than 40 hours?

(ii) More than 200 hours?

(ii). For a medical study, a researcher wishes to select people in the middle 50% of the

population based on blood pressure. Assuming that blood pressure readings are

normally distributed and the mean systolic blood pressure is 122 and the standard

deviation is 9, find the upper and lower readings that would qualify people to

participate in the study.

Expert Solution

orchestra answered 2 years ago

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