Centers and Variation

The double dot plot shows the number of hours that 12 basketball and 12 softball players spend exercising each month. Compare the centers and variations of the two populations. Which of the following inferences about the two populations is correct?

• The data for softball players has a mean of 24.5.

• The data for basketball players has a median of 24.

• Overall, the softball players exercise fewer hours each month, but they exercise a more consistent number of hours.

• Overall, the basketball players exercise fewer hours each month than softball players, but they exercise a more consistent number of hours.

The double box plot shows the number of cars that passed through two different intersections. Compare the centers and variations of the two populations. Which of the following inferences about the two populations is correct?

• The number of cars recorded in Intersection A are centered around a higher value.

• The number of cars recorded in Intersection B are centered around a higher value.

• The variation of data is greater for Intersection A.

• The data for the number of cars that pass through Intersection B is more consistent.

Students and teachers at Melton Middle School are having a walk-a-thon to raise money for the school. The dot plot shows the number of laps around the school that different teachers walked. What percent of the teachers walked fewer than 5 laps around the school?

• about 63.2%

• about 42.1%

• about 48.9%

• about 29.6%

The double box plot shows the number of cars that passed through two different intersections. Compare the centers and variations of the two populations. Which of the following inferences about the two populations is correct?

• The variation of Intersection A is 15.

• The variation of Intersection A is 10.

• The median of Intersection B is 80.

• The median of Intersection B is 70.

The double box plot shows the number of minutes that patients had to wait in the waiting room in two different doctors’ offices. Compare the centers and variations of the two populations. Which of the following inferences about the two populations is correct?

• In general, patients wait longer to see Dr. Newton.

• In general, patients wait longer to see Dr. Smith.

• There is a greater variation in the recorded wait times to see Dr. Newton.

• The median wait time is shorter to see Dr. Smith.

Ervin bowled 7 games last weekend. His scores are: 155, 165, 138, 172, 127, 193, 142. What is the sample standard deviation of Ervin's scores?

• 511.33

• 22.61

• 438.48

• 20.94

Compare the centers and variation.

• Math has a higher median (center) and more variation.

• Math has a higher median (center) and less variation.

• Math has a lower median (center) and less variation.

• Math has a lower median (center) and more variation.

From the boxplots it can be concluded that the diameters of the jellyfish taken from location A are generally

• Similar to the diameters taken from location B

• Less than the diameters taken from B and less variable

• Less than the diameters taken from B and more variable

• Greater than the diameters taken from B and less variable

• Greater than the diameters taken from B and more variable

All of the below sets have the same mean.
Set 1-Standard Deviation=3.1
Set 2-Standard Deviation=4.9
Set 3-Standard Deviation=1.7
Set 4-Standard Deviation=3.2
Which set of data probably has the points closest to the mean?

• 1

• 2

• 3

• 4

Which data set has the largest standard deviation?

• Set 1

• Set 2

• Set 3

• Set 4