Comparison and Inference Between Data

Coach Lantz recorded the number of shots on goal players made during two weeks of a lacrosse scrimmage. How much greater was week 2's mean than week 1's mean? Type your answer as a one-digit number without a label.

Brazil asks 7 classmates how many erasers and pens they carry in their bags. The mean number of erasers is 10. The mean number of pens is 4. What inference could Brazil make using this data?

• Most of Brazil's classmates carry more pens than erasers in their bags.

• All of Brazil's classmates carry more erasers than pens in their bags.

• Most of Brazil's classmates carry more erasers than pens in their bags.

• Most of Brazil's classmates carry similar amounts of erasers and pens in their bags.

The dot plots show the weights of a random sample of fish from two lakes. Pick the statement that describes the variability of the samples.

• The variability of the weights of the fish in Lake S is greater than the variability of the weights of the fish in Lake R.

• The variability of the weights of the fish in the two lakes are about the same.

• The variability of the weights of the fish in Lake R is greater than the variability of the weights of the fish in Lake S.

• You cannot determine variability based on a dot plot.

The table shows the finish times of 30 runners in the 100-meter dash. Use the table to identify the inference that can be made by comparing the measures of center.

• Every runner ran faster last year as compared to this year.

• Most runners ran faster last year, on average, as compared to this year.

• The runners ran faster this year, on average, as compared to last year.

• Every runner ran faster this year as compared to last year.

Match the following inference with the statistical measure that best justifies the inference:"The middle two quartiles of students in Grade 6 had greater variability in time spent doing homework last week than the middle two quartiles of students in Grade 8."

• Mean

• Median

• Range

• Interquartile Range (IQR)

Match the following inference with the statistical measure that best justifies the inference: "On average, students in Grade 8 spent 2 more hours last week doing homework than students in Grade 6."

• Mean

• Median

• Range

• Interquartile Range (IQR)

Match the following inference with the statistical measure that best justifies the inference: "The two students in the same grade that had the greatest difference in time spent doing homework last week are in Grade 8."

• Mean

• Median

• Range

• Interquartile Range (IQR)

Match the following inference with the statistical measure that best justifies the inference:"Half of the students in Grade 8 spent more time doing homework last week than at least half of the students in Grade 6."

• Mean

• Median

• Range

• Interquartile Range (IQR)

Mrs. Cox and Mr. Jones are in charge of the work-study program for Oak High School. Each teacher is in charge of supervising 10 students. They are comparing statistics for two groups of students based on the hours worked each week. Which statement is true?

• The mean for Mrs. Cox is greater than the mean for Mr. Jones.

• The median for Mr. Jones is greater than the median for Mrs. Cox.

• The median for Mrs. Cox is greater than the median for Mr. Jones.

• The both have the same mode.

Mr. Daniels was comparing two random samples of students test scores from his Advanced Algebra 1st and 3rd Block classes: 1st Block: Mean= 73.4; Standard Deviation= 6.5 3rd Block: Mean= 67.5; Standard Deviation= 12.4 What can Mr. Daniels most accurately conclude between overall class test scores of 1st and 3rd block?

• The students in both classes performed the same on the test.

• 3rd block's scores had a higher standard deviation, so they performed much better than 1st block

• 3rd block scores are more closely grouped around the average, therefore they had better scores than 1st block

• 1st block students tend to have a slightly better grasp of the material since the mean is higher and dispersion from the mean is less than 3rd block