Statistics Midterm Review

The given histogram shows the distribution of the percents of women aged 15 and over who have never married in each of the 50 states and the District of Columbia. The center of this distribution is in which interval?

• 22% to 24%

• 24% to 26%

• 26% to 28%

• 28% to 30%

• 36% to 38%

When a set of data has suspect outliers, which of the following are preferred measures of central tendency and of variability?

• mean and standard deviation

• mean and variance

• mean and range

• median and range

• median and interquartile range

• Mode
• Median
• Mean
• IQR

This uses a small group to gather information about the entire population

• census

• sample survey

• experiment

• observational study

We divide our school into two groups: first year students and others. We then take random samples from each group. This is an example of a

• simple random sample

• Stratified random sample

• Bad sampliing

• systematic random sample

What is the relative frequency of people that purchased no food?

• 10%

• 60%

• 15%

• 30%

Describing the shape of a data set that is a mirror image one both sides of the center point.

• symmetrical

• unimodal

• skewed

• uniform

If a number is added to the set that is in the middle of the data, how does this affect the range?

• increase

• decrease

• stays the same

• both increase and decrease

Describe the histogram:

• Left Skewed

• Symmetrical

• Right Skewed

• Uniform

The first quartile (Q 1) is the median of the lower half of the set.
The second quartile (Q 2) is the median of the whole set .
The third quartile (Q 3) is the median of the upper half of the set.

• All three statements are true.

• Only the 1st statement is true.

• Only the 2nd and the 3rd statements are true.

• Only the 3rd statement is true.