SmartExpert
$30/per page/Negotiable
MAT300 Unit 2 Milestone 2 Exam Answer Sophia Course
1
Sara wonders what percentage of her students answered at least half of the quiz questions incorrectly.
The relative cumulative frequency of students who earned a score of 21 or higher on the quiz is __________ %.
•
16
•
32
•
18
•
68
2
The midterm exam scores obtained by boys and girls in a class are listed in the table below.
What does the circled section represent?
•
Two boys scored between 80 and 89 marks on the exam.
•
Twelve boys scored 8 marks on the exam.
•
Eight boys scored over 10 marks on the exam.
•
Eight boys scored 12 marks on the exam.
3
Dave drives to work. While driving the car over nine days, he observes his daily average speed as 45, 62, 44, 70, 59, 66, 54, 63, and 67 miles per hour.
The median speed at which Dave drove to work was __________.
•
63 miles per hour
•
59 miles per hour
•
62 miles per hour
•
58.89 miles per hour
4
Which of the following statements is true for an outlier?
•
It is a data point that is below Q1 - 1.5 x IQR or above Q3 + 1.5 x IQR.
•
It is a data point that is between Q1 + 1.5 x IQR and Q3 - 1.5 x IQR.
•
It is a data point that is below or above Q1 ± 1.5 x IQR.
•
It is a data point that is below or above Q3 ± 1.5 x IQR.
5
Let x stand for the percentage of an individual student's math test score. 64 students were sampled at a time. The population mean is 78 percent and the population standard deviation is 14 percent.
What is the standard deviation of the sampling distribution of sample means?
•
64
•
0.22
•
1.75
•
14
6
Given the formula above, select the true statement for this data set: 4, 6, 6, 6, 9, 9, 12, and 12, with a mean of 8. Answer choices are rounded to the hundredths place.
•
The variance is 8.86 and the standard deviation is 7.50.
•
The variance is 8.86 and the standard deviation is 2.98.
•
The variance is 2.98 and the standard deviation is 8.86.
•
The variance is 7.50 and the standard deviation is 2.98.
7
At Jeremy's school, the final grade for his Human Biology course is weighted as follows:
Tests: 50%
Quizzes: 35%
Homework: 15%
Jeremy has an average of 94% on his tests, 78% on his quizzes, and 62% on his homework.
What is Jeremy's weighted average?
•
83.6%
•
78%
•
75.6%
•
74.8%
8
Nick just received his 20 question test back. He scored a 24 out of a possible 60 points. His teacher told him the mean score on the test was a 35, with a standard deviation of 6.
What is Nick's z-score?
•
4.17
•
-4.17
•
1.83
•
-1.83
9
A fast-food restaurant gave a “Customer Satisfaction Survey” in which 1500 customers rated how satisfied they were with service. The results are shown below as a table and pie chart.
Rating Frequency
Extremely Satisfied 234
Satisfied 443
Neutral 246
Dissatisfied 203
Extremely Dissatisfied 374
The relative frequency of people who were dissatisfied with the service is __________%.
•
29.5
•
20.3
•
13.5
•
38.5
10
When a survey was conducted among 100 students to find their favorite pizza topping, 45 students voted for pepperoni, 25 for mushrooms, and 30 voted for cheese.
If a pie chart were made showing the number of votes for each topping, the central angle for the cheese sector would be __________.
•
90°
•
198°
•
162°
•
108°
11
The graph below shows the change in passenger load factor for all scheduled airlines in the United States over different months of a year.
Which segment of the graph indicates no change in the passenger load?
•
A
•
C
•
B
•
D
12
The school paper published the results of a survey among grade eight students with regards to their favorite subject.
Which of the following statements about the stack plot is true?
•
More girls than boys chose English as their favorite subject.
•
Most of the students chose English as their favorite subject.
•
More boys chose math as their favorite subject than science.
•
More than half the girls chose science as their favorite subject.
13
The first quartile (Q1) value from the above box plot is __________.
•
33
•
40
•
29
•
52
14
In which of these cases should mode be used?
•
When the data has extreme values
•
When the data is represented using ratio scale
•
When the data is represented using interval scale
•
When the data is qualitative and we talk about the most frequent category
15
Which of the following statements is true?
•
For the Central Limit Theorem to be true, you must have a large sample, the underlying population must be normally distributed, and the standard deviation should not be finite.
•
For a large enough sample size, the Central Limit Theorem states that the sample means of repeated samples of a population are normally distributed.
•
For a large enough sample size, the Central Limit Theorem states that the sample medians of repeated samples of a population are normally distributed.
•
Even with a very large sample size, the Central Limit Theorem states that the sample means of repeated samples of a population cannot be normally distributed.
16
The dotplot below shows the number of songs Carly downloaded over 15 successive weekends.
What is the greatest number of songs downloaded?
•
5
•
8
•
10
•
9
17
For a class reading competition, the students were asked to read a book. Mike, Jack, and Rayon discussed the numbers of pages they read on the first day. One of them made a graph to represent the data.
Who made the graph, and why?
•
Mike, because he wanted to make the amount read by each person appear reasonably close.
•
Mike, because he wanted to accurately show the amount read by each person.
•
Rayon, because he wanted to make the amount read by each person appear very different.
•
Jack, because he wanted to make it look like he read significantly more than the others.
18
The mean of any standard normal distribution is __________.
•
0.5
•
1
•
0
•
±0.5
19
Select the false statement about standard deviation.
•
It is the square root of variance.
•
It is the average of the squared differences of the values from the mean.
•
It is calculated using the mean.
•
It is a measure of how spread out the values of a data set are.
20
The quality control inspector of a factory manufacturing screws found that the samples of screws are normally distributed with a mean length of 5.5 cm and a standard deviation of 0.1 cm.
If the distribution is normal, what percent of data lies between 5.3 centimeters and 5.7 centimeters?
•
99.7%
•
34%
•
95%
•
68%
21
Ralph records the time it takes for each of his classmates to run around the track one time. As he analyzes the data on the graph, he notices very little variation between his classmates’ times.
Which component of data analysis is Ralph observing?
•
The overall shape of the data
•
The overall spread of the data
•
The center of the data set
•
An outlier in the data set
22
Select the statement that is FALSE.
•
The range is never greater than the greatest value of a data set.
•
The interquartile range is the difference between the highest and lowest values in the middle of a data set.
•
The mean is never greater than the greatest value of a data set.
•
The range is the difference between the largest and smallest values of a data set.
23
Jerry graded seven standardized tests with scores of 60, 74, 41, 87, 94, 79, and 57.
Which standardized test score represents the 50th percentile?
•
57
•
41
•
74
•
79
24
Consider the histogram showing the weights of babies born in a hospital over a month.
What is the difference in the weights of the lightest baby and the heaviest baby born in the hospital?
•
7.5 pounds
•
5.5 pounds
•
3 pounds
•
6 pounds
25
Which of the following statements about a normal distribution is true?
•
The normal distribution is single-peaked and symmetric.
•
A large portion of the data is skewed to the right.
•
A large portion of the data is located near the tails.
•
The normal distribution is an example of a bimodal distribution.
26
Which of the following statements about a positively skewed distribution is true?
•
The mean, median, and mode have the same values.
•
The distribution of the data tails to the right of the median.
•
The distribution of the data features two modes.
•
The distribution of the data tails to the left of the median.