The dot plots represent the cost of first-year college tuitions for two different U.S. regions. Which of the statements are true?
I. Region 1 has a greater mean than region 2.
II. Region 2 has a greater median than region 1.
III. Region 1 has a greater interquartile range than region 2.
IV. Region 2 has a greater standard deviation than region 1.
A.
I and III
B.
I and II
C.
III and IV
D.
II and IV
B. I and II
Explanation:
I. Region 1 has a greater mean than region 2: This statement is true if the dots in region 1 are on average higher than the dots in region 2.
II. Region 2 has a greater median than region 1: This statement is true if the middle dot in region 2 is higher than the middle dot in region 1.
III. Region 1 has a greater interquartile range than region 2: The interquartile range is the range of the middle 50% of the data. This statement is not necessarily true based on the dot plots alone.
IV. Region 2 has a greater standard deviation than region 1: The standard deviation measures the spread of data around the mean. This statement is not necessarily true based on the dot plots alone.