SOLUTION: Samples of size n = 240 are randomly selected from the population of numbers (0 through 20) produced by a random-number generator, and the variance is found for each sample. What i

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Question 1150855: Samples of size n = 240 are randomly selected from the population of numbers (0 through 20) produced by a random-number generator, and the variance is found for each sample. What is the distribution of the sample variances?

A)skewed to the left


B)normal (approximately)


C)skewed to the right


D)not enough information provided
Found 2 solutions by MathLover1, jim_thompson5910:
Answer by MathLover1(20849) About Me  (Show Source):
You can put this solution on YOUR website!


skewed to the right would have to make it a good 80 by 90 by 80 by 90 by 80 which would be 4+4 and make that 69
answer: C)skewed to the right

Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!

The sample size n = 240 satisfies the inequality n > 30.

So the distribution of sample variances will be approximately normal according to the Central Limit Theorem (CLT). This theorem says that whenever n > 30, then the distribution of sample means, sample variances, etc will be approximately normal. This is handy when doing things like finding areas under the curve to determine P values.

Answer: B) normal (approximately)

side note: I honestly don't know what the tutor @MathLover1 is referring to when they wrote "would have to make it a good 80 by 90 by 80 by 90 by 80 which would be 4+4 and make that 69". It's possible they mixed up two problems together.