w10_Sampling_post

w10_Sampling_post - has been exceeded. Suppose the maximum...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
(PS3, Q1) The following probability distribution of the monthly incomes (x in $1000) of account executives has been estimated for a big accounting firm. a. Find the expected value and the standard deviation of the monthly incomes. b. A random sample of 64 executives is taken. What is the probability that the sample mean value exceeds $20,500?
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
(PS3, Q11) The monthly sales of Dark-Man Toothpaste are believed to be normally distributed with a mean of 1,000 tubes and a standard deviation of 150 tubes. a. What is the probability that more than 1,100 tubes will be sold in the next month? b. To have a 95% probability that the company will have sufficient stock to cover the monthly demand, how many tubes should be produced? c. What is the probability that the total sales in the next year is over 12,600 tubes? Assume that the sales of the 12 months are independent.
Background image of page 2
(PS3, Q12) Companies that purchase parts from suppliers often specify the maximum allowable proportion of defective parts. Random sampling is used to decide whether this limit
Background image of page 3
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: has been exceeded. Suppose the maximum allowable proportion defective for a purchase of computer chips is 0.03. An inspection plan has been devised, based on a random sample of 300 chips. If 3% or more defective chips are found (i.e. ≥ 0.03), the entire lot is deemed unacceptable and is inspected in its entirety at the supplier’s expense. Suppose a batch of 10,000 chips contains 1.9% defective chips (this would be unknown to both supplier and purchaser, since the batch has not been inspected). Note that this is an acceptable proportion of defectives. a. Find the mean and the variance of the sample proportion . b. Find the probability that the lot will be deemed unacceptable, i.e., P( ≥ 0.03). c. Now suppose there are five large batches, each containing 1.9% defective chips. What is the probability that exactly two batches will be deemed unacceptable?...
View Full Document

This note was uploaded on 01/01/2010 for the course ISOM ISOM111 taught by Professor Anthonychan during the Spring '09 term at HKUST.

Page1 / 3

w10_Sampling_post - has been exceeded. Suppose the maximum...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online