The weights of all the students in grade 9 are arranged from least to greatest. Which statistical measure separates the top half of this set of data from the bottom half?
1) mean
2) mode
3) median
4) Interquartile range
What is 3?
To select a new school mascot, 20 randomly selected students in each grade were asked to choose between the two finalists: tiger and eagle. The results are:
Grade 5: {Tiger =14; Eagle =6}
Grade 6:{Tiger =13; Eagle = 7}
Grade 7:{Tiger = 8 ; Eagle = 12}
Grade 8:{Tiger = 5; Eagle = 15}
Which statement is best supported by the results?
A) The preferred mascot is a tiger.
B) The preferred mascot is an eagle.
C) Fifth and sixth grade students at the school preferred an eagle mascot.
D) Seventh and eighth grade students at the school preferred an eagle mascot.
What is D?
Sample
What is "a set of individuals or values chosen from a population"?
Which statement is true about the data set 3, 4, 5, 6, 7, 7, 10?
1) mean = mode;
2) mean > mode;
3) mean = median;
4)mean < median
What is 3?
Random Sample
What is a sample selected in a way that gives every different possible sample of the same size an equal chance of being selected? (or a similar definition)
Mr. Taylor raised all his students’ scores on a recent test by five points. How were the mean and the range of the scores affected?
A) The mean increased by five and the range increased by five.
B) The mean increased by five and the range remained the same.
C) The mean remained the same and the range increased by five.
D) The mean remained the same and the range remained the same.
What is B?
Find the mean, median and mode in the following test scores: 15, 16, 17, 17, 17, 17, 14, 15, 15, 16, 20, 21, 22, 22
What is
Mean: 17.4
Median: 17.5
Mode: 17?
A school wants to add a coed soccer program. To determine student interest in the program, a survey will be taken. In order to get a random sample, which group should the school survey?
A) every third student entering the building
B) every member of the varsity football team
C) every member in Ms. Zimmer’s drama classes
D) every student having a second-period French class
What is A?
Inference
What is using data from a sample to draw conclusions about a population? (or a similar definition)
Find the range and outliers from the following exam scores: 87, 56, 57, 65, 34, 66, 75, 67, 87, 99, 84, 73, 79, 80
What is
Range = 65 and Outliers: 34 and 99?
Mr. Vargas is trying to compare the exam scores of his 7th grade classes. He chose some students from both 71M and 72M. The scores for 71M were: 65, 85, 75, 90, 82, and 95. The scores for 72M were: 75, 74, 71, 95, 99, 85 and 75. What conclusion can Mr. Vargas reach about his two classes?
A) 72M had a higher median score than 71M.
B) 71M had a higher mean than 72M.
C) 71M had a greater range than 72M.
D) 72M had a greater mean absolute deviation than 71M.
What is C?
Four hundred licensed drivers participated in the math club's survey on driving habits. These were the age groups and the number of the participants: 16-25 years old = 150; 26-35 years old = 129; 36-45 years old =33; 46-55 years old = 57 ; 56-65 years old = 31.
A) It may be biased because no one younger than 16 was surveyed.
B) It would be fair because many different age groups were surveyed.
C) It would be fair because the survey was conducted by the math club students.
D) It may be biased because the majority of drivers surveyed were in the younger age intervals.
What is D?
Measures of center
What are values at the center or middle of a data set? Examples: Mean, Median, and Mode.
What is the IQR for the following data set? A={3, 6, 5, 10, 15, 26,13, 15}
What is 9.5?
Find the mean of the IQR for the following set of data: 23, 24, 22, 30, 25, 26, and 32. Round the answer to the nearest tenth.
What is 26.5?
Clusters
What is a group of data that does not match the rest of the data?