Statistics (central tendency)

The prices at several different stores for a pair of shoes are shown below.
$78, $79, $81, $82, $83
Two days later, another store has the same shoes on sale for $65. How does the new price affect the data?

• Only the range was affected.
• The median increased, and the range increased.
• The mean increased, and the range increased.
• The mean decreased and the range increased.

The data set below has an outlier of 42.
2, 5, 12, 15, 19, 4, 6, 11, 16, 18, 12, 12, 42
What effect does removing the outlier have on the distribution of the data?

• The mean will decrease
• The median will decrease
• The mean will increase
• The median will increase

Gabriella’s quiz grades are shown below.
88, 92, 92, 96, 98
Gabriella scored a 20 on her sixth quiz. What effect does this score have?

• The low score causes the median to increase.
• The low score causes the median to decrease.
• The low score causes the mean to increase.
• The low score causes the mean to decrease.

If 20 is added to the data set below, which statement will be true?
50, 55, 55, 60, 62

• The median will be 20
• The mode will increase
• The mean will increase
• The mean will decrease

The table below shows the lengths of fences a company installed during a week. 
Which statement is true?

• The 275-foot fence caused the mean to be significantly lower than the median.
• The 275-foot fence caused the median to be significantly lower than the mean.
• The 2,250-foot fence caused the mean to be significantly greater than the median.
• The 2,250-foot fence caused the median to be significantly greater than the mean.

Jacob recorded the ages of the people at a picnic. The data set is listed below.
12, 12, 14, 15, 16, 20, 24, 28, 32, 35, 36
What effect does the arrival of Jacob’s 72-year old grandfather have on the difference between the mean and the median ages of people at the picnic?

• The difference increases by about 2.1.
• The difference increases by about 3.3
• The difference increases by about 4.1
• The difference increases by about 4.3

Which box and whisker plot has the smallest lower quartile (Q1)?

• Top plot
• Bottom plot

Which box and whisker plot has the highest median?

• Top plot
• Bottom plot

What percent of students have a height between 58 inches and 60 inches?

• 25%
• 50%
• 75%
• 100%

What percent of students have heights between 60 inches and 66 inches?

• 75%
• 50%
• 100%
• 25%