Sample MC Questions
Vocabulary
Probability and Error
Inference
Probability Basics
100
Which of the following distributions are more likely to be skewed to the right? I. Household prices II. Home prices III. Ages of teenage drivers
What is I and II
100
A method of data collection that involves separating samples into different strata based on covariate characteristics.
What is stratified sampling
100
A student reasons that he will or will not receive a 5 on the AP Statistics Exam, and therefore the probability of receiving a 5 is .50. Why is this incorrect reasoning?
The events are not equally probable.
100
df= (r-1) (c-1)
What is the formula for degrees of freedom when conducting a chi square test for independence.
100
You roll two dice. What is the probability that the sum is 6 given that one die shows a 4?
What is 2/11
200
Which of the following are true statements? I. All symmetric histograms have single peaks II. All symmetric bell-shaped curves are normal III. All normal curves are bell-shaped and symmetric
What is III only
200
A method of sampling in which the researcher divides the population into separate groups, then a simple random sample of groups is selected from the population.
What is cluster sampling
200
According to a CBS poll taken in 1992, 15% of the public have responded to a telephone call-in poll. In a random group of five people, what is the probability that exactly two have responded to a call-in poll?
What is .138
200
A geneticist claims that four species of fruit flies should appear in the ratio 1:3:3:9. Suppose that a sample of 2000 flies contained 110,345,360, and 1185 flies of each species. Is there sufficient evidence to reject the geneticist's claim?
The data gives sufficient evidence to reject the geneticist's claim.
200
It turns out that 25 seniors at Fashionable High School took both the AP Statistics exam and the AP Spanish Language exam. The mean score on the Statistics exam for the 25 seniors was 2.4 with a standard deviation of 0.6 and the mean score on the Spanish Language exam was 2.65 with a standard deviation of 0.55. We want to combine the scores into a single score. What are the correct mean and standard deviation of the combined scores?
5.05; you cannot determine the standard deviation from this information.
300
Suppose the average score on a national test is 500 with a standard deviation of 100. If each score is increased by 25%, what are the new mean and standard deviation?
What is 625 and 125
300
A general statistical term meaning a systematic favoring of certain outcomes.
What is bias
300
A pharmaceutical company claims that a medicine will produce a desired effect for a mean time of 58.4 minutes. A government researcher runs a hypothesis test of 40 patients an calculates a mean of 59.5 minutes with a standard deviation of 8.3 minutes. What is p-value?
What is 2P(t>.838)
300
Suppose H0:p=.4 and the power of the test for the alternative hypothesis p=.35 is .75. What is the probability of failing to reject H0?
What is .25
300

The 2000 Census identified the ethnic breakdown of the state of California to be approximately as follows: White: 46%, Latino: 32%, Asian: 11%, Black: 7%, and Other: 4%. Assuming that these are mutually exclusive categories (this is not a realistic assumption, especially in California), what is the probability that a random selected person from the state of California is of Asian or Latino descent?

What is 43%

400
If quartiles Q1=20 and Q3=30, which of the following must be true? I. The median is 25 II. The mean is between 20 and 30 III.The standard deviation is at most 10
What is none of the above
400
The relative frequency of an event is the proportion of times the event happened, that is, the number of times the event happened divided by the total number of trials.
What is the law of large numbers
400
A school superintendent must make a decision whether or not to cancel school because of a threatening snow storm. What would the results be of Type I error?
What is weather remains dry, but school is needlessly cancelled.
400
Which is typically more severe, Type I or Type II error?
What is Type II error
400
You own an unusual die. Three faces are marked with the letter "X," two faces with the letter "Y," and one face with the letter "Z." What is the probability that at least one of the first two rolls is a "Y"?
What is 5/9
500
When a set of data has suspect outliers, what are the preferred measures of central tendency and variability?
What is median and IQR
500
The probability and event will occur given that another event has occurred.
What is conditional probability
500
What is the probability of mistakenly failing to reject a false null hypothesis when a hypothesis test is being conducted at the 5% significance level?
There is insufficient information
500
The probability that it correctly rejects the null hypothesis when the null hypothesis is false
What is power
500
The GPA (grade point average) of students who take the AP Statistics exam are approximately normally distributed with a mean of 3.4 with a standard deviation of 0.3. Using Table A, what is the probability that a student selected at random from this group has a GPA lower than 3.0?
What is 0.0918