Normal Table Statistics

Find the standard error, Sx1-x2, to test the claim that μ1 = μ2. Two samples are random, independent, and come from populations that are normal. The sample statistics are given below. Assume that σ2 1 = σ2 2. Use α = 0.01. Use the formula above.

n1 = 14 n2 = 12

x1 = 15 x2 = 16

s1 = 2.5 s2 = 2.8

• 1.039

• 1.923

• 1.712

• 1.091

A pet association claims that the mean annual cost of food for dogs and cats are the same. The results for samples for the two types of pets are shown below. At α = 0.05, can you reject the pet​ association's claim? Assume the population VARIANCES ARE EQUAL. Assume the samples are random and independent, and the populations are normally distributed.

(Hint: Must use the standard error and t - formulas found in your notes for 8.2 Part 2 or must use graphing calculator).

• Fail to reject Ho, there is NOt enough evidence to SUPPORT the claim.

• Fail to reject Ho, there is NOt enough evidence to REJECT the claim.

• Reject Ho, there is enough evidence to REJECT the claim.

• Reject Ho, there is enough evidence to SUPPORT the claim.

Find the standard error, Sx1-x2, to test the claim that μ1 >μ2. Two samples are random, independent, and come from populations that are normal. The sample statistics are given below. Assume that σ2 1 = σ2 2. Use α = 0.01. Use the formula above.

n1 = 18 n2 = 13

x1 = 600 x2 = 585

s1 = 40 s2 = 25

• 10.546

• 12.590

• 12.103

• 11.763

It is a distribution in which the sets of data are clustered at the center and it formed like a bell-shaped curve.

• Discrete Probability Distribution

• Probability Distribution

• Normal Distribution

Which of the following is TRUE about normal curve distribution?

• Mean=Median=Mode

• Mean>Median>Mode

• Mean<Median<Mode

• Mean<Median>Mode

What is the sum of the area under the Normal Distribution curve?

• 0.997

• 1

• 13.5%

• 0.68

If a random variable x is greater than the mean, then which of the following is TRUE about the z-score?

• The z-score is at the left side of the mean.

• The z-score is at the right side of the mean.

• The z-score is the same position as the mean.

• The z-score is either on the left side or on the right side of the mean.

Which of the following is TRUE about standard normal distribution?

• μ=0 and σ=0

• μ=0 and σ=1

• μ=1 and σ=1

• μ=1 and σ=0

What is the area that falls within 2 standard deviations from the mean?

• 0.997

• 1

• 95%

• 0.68

Which of the following is NOT a characteristic of a normal curve distribution?

• The curve symmetrical about the mean

• The mean, median, and mode are not equal

• The curve extends indefinitely to both sides

• The total area under the normal curve is 100%