(variance is the sample deviation, squared)

0.489, 0.561

P-hat (I can’t do the hat on here) can be found by adding the two confidence intervals together and dividing them by two. E can be found by subtracting the smaller from the larger and dividing by two.

A 95% level of confidence has α = 0.05 and critical value of zα/2 = 1.96.

A 99% level of confidence has α = 0.01 and critical value of zα/2 = 2.58.

A 99.5% level of confidence has α = 0.005 and critical value of zα/2 = 2.81

also, remember standard deviations are like rulers. they are just a measuring device of how far away you’ve gotten from the mean, and in what direction

Interpret the estimated y-intercept of the line.

y(hat)= 14000 + 2000x

>for an administrator who is rated zero, what is the raise?

The number of cups of coffee sold in a cafeteria during lunch

95% confidence; n = 2428, x = 1704

The sample size is n = 200 and σ = 19

The sample size is n = 4, σ = 12.7, and the original population is normally distributed.

A random sample of 105 light bulbs had a mean life of 441 hours with a standard deviation of 40 hours. Construct a 90% confidence interval for the mean life, μ, of all light bulbs of this type. (round to whole numbers)

A laboratory tested twelve chicken eggs and found that the mean amount of cholesterol was 225 milligrams with s = 15.7 milligrams. Construct a 95% confidence interval for the true mean cholesterol content of all such eggs.

(round to whole #s)

(round to one decimal)

α = 0.09 for a right-tailed test.

A) There is not sufficient evidence to support the claim that the mean is less than 30 miles per gallon.

B) There is not sufficient evidence to support the claim that the mean is greater than 30 miles per gallon.

C) There is sufficient evidence to support the claim that the mean is less than 30 miles per gallon.

Correct Response

D) There is sufficient evidence to support the claim that the mean is greater than 30 miles per gallon

A) Fail to reject the claim that the percentage of children who suffer from the disorder is equal to 6% when that percentage is actually different from 6%.

B) Reject the claim that the percentage of children who suffer from the disorder is different from 6% when that percentage really is different from 6%.

Correct Response

C) Reject the claim that the percentage of children who suffer from the disorder is equal to 6% when that percentage is actually 6%.

D) Fail to reject the claim that the percentage of children who suffer from the disorder is equal to 6% when that percentage is actually 6%.

3 decimals.

If 7% of the thermometers are rejected because they have readings that are too high, but all other thermometers are acceptable, find the temperature that separates the rejected thermometers from the others. (2 decimals)

A)

mutually exclusive and independent.

B)

not mutually exclusive.

C)

independent.

D)

mutually exclusive and dependent.

P(A) = 0.6, P(B) = 0.3, and P(A and B) = 0.17