AP Statistics Review

A slice of pizza from a certain restaurant has an average area of 40 square inches with a standard deviation of  5 square inches.  Assuming the distribution of areas is approximately normal, what proportion of slices will be between 35 and 50 square inches

• 68%

• 34%

• 81.5%

• 95%

If a distribution is symmetrical, which of the following is true?

• the mean must be less than the median

• the mean and median must be equal

• the mean must be greater than the median

• the mean is either equal to or less than the median

• it's impossible to tell which of the above statements is true without seeing the data

The side-by-side boxplots show the distribution of test scores in Ms. Williams’s two sections of calculus. Based on these boxplots, which one of the following statements must be true?

• The lowest score in A period was close to the 15th percentile of the C period class.

• The mean score for students in C period was higher than the mean score for students in A period.

• More people scored between 72 and 90 in C period than scored between 72 and 81 in A period.

• The standard deviation of scores in A period is smaller than the standard deviation of scores in C period.

• A

• B

• C

• D

• E

Is this a probability distribution?

• No, the sum of p(x) does not equal 1.

• Yes, all p(x) are between 0 and 1.

• No, all p(x) are not between 0 and 1.

• Yes, the sum p(x) is 1.

Is this a probability distribution?

• No

• Yes

• A

• B

• C

• D

• E

The histogram below displays the frequencies of waiting times, in minutes, for 175 patients in a dentist's office.<\/p>

Which of the following could be the median of the waiting times, in minutes?<\/p>

• 2.5<\/p>

• 7.25<\/p>

• 12.25<\/p>

• 15<\/p>

• 17.50<\/p>

The histogram above shows the number of minutes needed by 45 students to finish playing a computer game.

Which of the following statements is correct?

• The distribution is skewed to the right.

• The distribution is skewed to the left.

• The distribution appears to be normal.

• The distribution appears to be chi-square.

• The distribution appears to be uniform.

Data were collected on the amount, in dollars, that individual customers spent on dinner in an Italian restaurant. The quartiles for these data are given in the picture. Which of the following statements must be true for these customers?

• At least half of the customers spent less than or equal to $44.27 and at least half spent greater than or equal to $44.27.

• Seventy-five percent of the customers spent between $36.27 and $58.97.

• Twenty-five percent of the customers spent less than or equal to $58.97 and the remaining 75 percent spent greater than or equal to $58.97.

• The mean amount spent by customers is $44.27.

• A majority of customers spent $44.27.