Measures of Center and Spread

The mean, median and standard deviation of four data sets are shown below. Which statement about the data sets is correct?

• Data set B and data set C are both positively skewed.

• Data set A and data set D are both negatively skewed.

• Only data set C is positively skewed.

• Only data set A is negatively skewed.

In a survey, the median number of hours students spent on homework in 7 schools was 8. Which statement must be true about this survey?

• The students spent 8 hours on homework in at least 1 school.

• The students spent exactly 8 hours on homework in at least two of the schools.

• The total number of hours spent on homework across all schools was 56.

• The average number of hours spent on homework per school was 8.

Tags

CCSS.7.EE.B.3

A dot plot titled "Swimming Competition Times" displays times (in seconds) ranging from 52 to 62. A time of 48 seconds is later added to the data set. After the time of 48 seconds is added, how does the mean change?

• The mean increases

• The mean stays the same.

• The mean cannot be determined.

• The mean decreases.

A study examines the positive association between the number of hours students study per week and their test scores. Which scatter plot most likely represents the data from the study?

• SCATTER PLOT A

• SCATTER PLOT B

• SCATTER PLOT C

• SCATTER PLOT D

Tags

CCSS.HSN.VM.C.6

What is the BEST information that can be gathered from the scatter plot below?

• Students who get more sleep enjoy sleeping better than students who get less sleep.

• All students who sleep 8 hours per night will have the same GPA.

• There is no relationship between sleep duration and academic performance.

• Students who get adequate sleep tend to have higher grade point averages than students who get less sleep.

Tags

CCSS.8.SP.A.1

Marcus is investigating the relationship between the amount of water plants receive and their growth height. Each week he waters his plants with different amounts and measures how tall they grow. He displays his results in a scatter plot. Which of the following is the most appropriate quantity to use on the x-axis of the scatter plot?

• The height of the plants in centimeters.

• The week he measures the plants.

  
  

• The amount of water the plants receive in milliliters.

• The type of plant species he is growing.

  
  

Tags

CCSS.8.SP.A.1

A fitness coach studies the relationship between hours spent training per week and the number of injuries sustained over a season. The coach plots results from several athletes on a scatter plot and draws a line of best fit through the data. The equation of the line of best fit is y = 0.85x+2.5, where x is the number of hours spent training per week and y is the number of injuries sustained. Which is a true statement according to the equation?

• For every 1 hour increase in training per week, the number of injuries will increase by an average of 0.85 injuries.

• If an athlete trains 2.5 hours per week, the average number of injuries sustained will be 0.

• For every 0.85 hours of training, the number of injuries will increase by an average of 1 injury.

• If 0 hours of training is done, the average number of injuries sustained will be 0.85.

Tags

CCSS.8.SP.A.3

The scatter plot below shows the number of hours students studied and their test scores in Mr. Chen's algebra class.

Which function, f(h), approximates the student's test score, f, as a function of hours studied, h?

• f(h) = 4.8h + 48

• f(h) = h + 50

• f(h) = 6.1h + 45

• f(h)= 5.2h + 52

Tags

CCSS.HSF.LE.B.5

Consider the scatter plot shown. What best describes the relationship between x and y?

• linear and weak

• exponential and strong

• exponential and weak

• linear and strong

Tags

CCSS.HSF-LE.A.1A

A park ranger records the number of visitors to a nature trail each day. The visitor counts for 15 days are shown on the line plot shown.

On the next day, 51 visitors came to the trail. How does this day change the statistics that summarize the data?

Choose ALL that are correct.

• The mean increases.

• The median increases.

• The range increases.

• The standard deviation increases.

• The interquartile range increases.