Stats: Exploratory Data Analysis Study Guide

Which of the following is the best description of the data used to generate this histogram? (Note that the horizontal axis has no scale, so you will make your choice based solely upon the histogram's shape.)

Match the following

• Shoe sizes of 1,000 men and women

• 
• SAT Math scores of 1,000 future engineer

• 
• Cholesterol levels of 1,000 adults

• 
• Prices of 1,000 California homes

• 
• Results of rolling a six-sided die 1,000

• 

How many of the students surveyed eat at least 4 servings of fruits and vegetables daily?

• 4

• 8

• 12

• 20

Answer explanation

"At least 4" means "4 or more," which is 8 + 3 + 1 = 12.

Tags

CCSS.6.SP.B.4

CCSS.HSS.ID.A.1

What percentage of the students surveyed eat no more than 3 servings of fruits and vegetables daily?

• 31.2%

• 20

• 68.8%

• 62.5%

Answer explanation

There are 20 students who eat no more than 3 servings daily and a total of 32 students. So, 20/32 = 0.625, or 62.5%.

Tags

CCSS.6.SP.B.4

CCSS.HSS.ID.A.1

What proportion of the students surveyed eat exactly 5 servings of fruits and vegetables daily?

• 0.094

• 0.063

• 0.156

• 2

Answer explanation

There are 3 students who ate exactly 5 servings of fruits and vegetables daily and a total of 32 students. So, 3/32 = 0.09375, which can be rounded to 0.094.

Tags

CCSS.7.SP.A.2

How many of the people surveyed make less than 9 phone calls daily?

• 3

• 27

• 32

• 9

Answer explanation

The frequencies between 1 and 8 calls add up to 27, 16 + 11 = 27.

Tags

CCSS.6.SP.B.4

CCSS.HSS.ID.A.1

How many people were surveyed?

• 226

• 20

• 36

• 7.2

Answer explanation

The total number of people surveyed is found by adding up all the frequencies: 16 + 11 + 5 + 3 + 1 = 36 people.

Tags

CCSS.6.SP.B.5A

The ​ ​ ​ (a)   is a simple but useful visual display of quantitative data. Its principal virtues are:

• Easy and quick to construct for small, simple datasets.

• Retains the actual data.

• Sorts (ranks) the data.

• Stemplot
• Histogram
• Boxplot
• Dot plot
• Pie Chart

Here are the number of hours that 9 students spend on the computer on a typical day:

1 6 7 5 5 8 11 12 15

The mode number of hours spent on the computer is___

Answer explanation

Since 5 occurs twice in the sample, it is the most frequently occurring score.

Tags

CCSS.6.SP.B.5C

Here are the number of hours that 9 students spend on the computer on a typical day:

1 6 7 5 5 8 11 12 15

The mean number of hours spent on the computer is___

(rounded to the nearest hundredths)

Answer explanation

The mean involves the sum of all the observations (1 + 6 + 7 + 5 + 5 + 8 + 11 + 12 + 15 = 70) divided by the total number of observations (9), which equals 7.78.

Tags

CCSS.6.SP.B.5C

Here are the number of hours that 9 students spend on the computer on a typical day:

1 6 7 5 5 8 11 12 15

The median number of hours spent on the computer is___

(rounded to the nearest hundredths)

Answer explanation

After you order the data, since n = 9, the median is (9 + 1)/2 = 5, or the 5th observation in the ordered list, which in this case is 7.

Tags

CCSS.6.SP.B.5C