need math help

Topics: Sampling distribution for a mean (20 points)

Background

In this assessment you’ll work to solve homework-like problems, post your answers to the discussion forum, then have an opportunity to improve your answers.

To do: 

Complete the questions below. Explain how you arrived at your answer using lots of details. Your goal is to convince your instructor you understand what is going on, but also to help your classmates.

Read each question carefully to make sure you have answered all parts. Some parts have two questions per line.

Question #1 (10 points)

The amount of fill (weight in ounces) put into a glass jar of spaghetti sauce is normally distributed with a mean of μ=850 grams and σ=8 grams. The words "describe the distribution" mean to describe or compute the shape, mean, and spread of the distribution.

a) Find the probability that one jar selected at random contains between 848 and 855 grams. Also, give the shape, center, and spread of the model you used to answer this question.

b) Suppose that a sample of 24 jars of sauce have been selected. Find the probability that a random sample of 24 jars has a mean weight between 848 and 855 grams. Also, give the shape, center, and spread of the model you used to answer this question.

c) Why is the answer to part (b) much more than the answer to part (a)? (Hint, draw a picture!)

Question #2 (10 points)

The local bakery bakes more than a thousand 1-pound loaves of bread daily, and the weights of these loaves varies. The mean weight is 1 lb and 1 oz, or 482 grams. Assume the standard deviation of the weights is 18 grams and a sample of 40 loaves is to be randomly selected.

a) What is the shape, center, and spread of the model that you'll use to answer this question?

b) What is the probability that this sample mean will be between 475 and 495 grams?

c) What is the probability that the sample mean will have a value less than 478 grams?

d) What is the probability that the sample mean will be within 5 grams of the mean?

Turn in:

Contribute (20 points, itemized above)

Reply to the Module 6 Option B discussion forum with the responses to the question above. After you've "turned in" your assignment to the discussion topic, read through what other classmates have written. If you need to,

· reply to your own post with changes you'd need to make to get a correct solution

· explain why you didn't get a correct answer in the first place.

Reply (0 points)

Did someone do a particularly awesome job? Did you find a mistake? Reply to your classmate and let them know!

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