Stats Section 2.1 and 2.2

• A

• B

• C

• D

• E

Jorge's score on Exam 1 in his statistics class was at the 64th percentile of the scores for all students. His score falls

• between the minimum and first quartile

• between the first quartile and the median

• between the median and the third quartile

• between the third quartile and the maximum

• at the mean score for all students

When Sam goes to a restaurant, he always tips the server $2 plus $10% of the cost of the meal. If Sam's distribution of meal costs has a mean of $9 and a standard deviation of $3, what are the mean and standard deviation of his tip distribution?

• $2.90, $0.30

• $2.90, $2.30

• $9.00, $3.00

• $11.00, $2.00

• $2.00, $0.90

Scores on the ACT college entrance exam follow a Normal distribution with mean 21 and standard deviation 5. Wayne's standardized score on the ACT was -0.6. What was Wayne's actual ACT score?

• 3

• 13

• 16

• 18

• 24

For the density curve shown, which of the following statements is true?

• The mean is larger than the median.

• The proportion of outcomes between 0.2 and 0.5 is equal to 0.3.

• The proportion of outcomes greater than 1.5 is equal to 0.25.

An office uses two brands of fluorescent light bulbs in its overhead light fixtures. From past experience, it is known that Brand A bulbs have a mean life length of 3000 hours and a standard deviation of 200 hours, while Brand B bulbs have a mean life length of 2700 hours and a standard deviation of 250 hours. Which bulb has a longer life relative to all bulbs of its brand, a Brand A bulb that lasts 3150 hours or a Brand B bulb that lasts 2850 hours?

• The Brand A bulb has a longer life relative to its brand.

• The Brand B bulb has a longer life relative to its brand.

• The two bulbs have equally long lives.

Javier’s school bus is always late. Below are data on how many minutes late the bus was for 15 days in February. What is the 60th percentile of this distribution? *

1 2 2 2 3 3 4 4 4 5 6 7 8 10 12

• 3

• 4

• 5

• 6

Fuji apples grown at a certain orchard have a mean weight of 5.2 ounces with a standard deviation of 0.8 ounces. Suppose the scale the orchard owner uses systematically over weighs apples by 0.2 ounces and also weighs the apples in grams, rather than ounces. What would the mean and standard deviation of these apples’ weights be as determined by this scale? (Note: 1 ounce ≈ 28 grams).

• Mean 145.6 grams, standard deviation 22.4 grams.

• Mean 140 grams, standard deviation 22.4 grams.

• Mean 140 grams, standard deviation 16.8 grams.

The distribution of scores on the math section of the SAT (out of 800) follows an approximately Normal distribution with a mean of 508 and standard deviation of 110. What percent of students score between 398 and 728 points?

• about 81.5%

• about 50%

• about 83.85%

• about 95%

• about 68%

In the class of 2016, more than 1.6 million students took the SAT. The distribution of scores on the math section (out of 800) follows an approximately Normal distribution with a mean of 508 and standard deviation of 110. About what 95% of students who took the SAT scored between _______ and _______?

• 398 and 618

• 288 and 728

• 398 and 728

• 288 and 618