Statistics and Probability Exam

Which of the following is a method of selecting a sample where every member of the population has an equal chance of being selected?

• Stratified sampling

• Simple random sampling

• Systematic sampling

• Cluster sampling

The mean of the data set {4, 8, 6, 5, 3} is:

• 4

• 5.2

• 5.5

• 6

In the data set {3, 7, 7, 2, 5}, what is the mode?

• 2

• 3

• 5

• 7

What is the median of the data set {12, 15, 11, 10, 14}?

• 11

• 12

• 13

• 14

Which of the following represents the first quartile (Q1) in a data set?

• The median of the entire data set

• The median of the lower half of the data set

• The median of the upper half of the data set

• The average of the data set

According to the empirical rule, what percentage of data falls within one standard deviation of the mean in a normal distribution?

• 50%

• 68%

• 95%

• 99.7%

In a normal distribution, what is the shape of the curve?

• Skewed left

• Skewed right

• Bell-shaped

• Uniform

What does the correlation coefficient measure?

• The slope of a line

• The strength and direction of a linear relationship

• The mean of a data set

• The variability of a data set

The addition rule in probability is used to find the probability of:

• Two independent events occurring together

• Either of two events occurring

• A single event occurring

• Two mutually exclusive events occurring together

The multiplication rule in probability is used to find the probability of:

• Either of two events occurring

• A single event occurring

• Two independent events occurring together

• Two mutually exclusive events occurring together