Examine the following survey question for any sources of bias. Given humanity's great tradition of exploration, do you favor continued funding for space flights? Is the question biased?

• Yes
• No

Submit QuestionQuestion 1Unattempted Question 2Check0/5 ptsRetries4Reattempts3InfoDetailsThe histogram below shows the distances (in meters) of all qualifying throws for the men's discus event at the 2004 Summer Olympics. Which of the following terms apply to this histogram? (Select all that apply.)

• symmetric
• negatively skewed
• bimodal
• uniform
• unimodal
• positively skewed

Which measure of center is most appropriate for this data?

• mean
• median

Which measure of spread is most appropriate for this data?

• range
• IQR
• standard deviation

Submit QuestionQuestion 2Unattempted Question 3Check0/5 ptsRetries4Reattempts3InfoDetails

What are two important first steps in data analysis?

• Cleaning the data and exploring it
• Cleaning and scrubbing the data
• the box plot and the 5 number summary
• correlation and regression

Submit QuestionQuestion 3Unattempted Question 4Check0/5 ptsRetries4Reattempts3InfoDetailsWhich of the following statements isfalse?

• Two independent events cannot occur at the same time.
• Two complementary events cannot occur at the same time.
• Two disjoint events cannot occur at the same time.

Submit QuestionQuestion 4Unattempted Question 5Check0/5 ptsRetries4Reattempts3InfoDetailsSuppose that 31% of people own dogs. If you pick two people at random, what is the probability that they both own a dog? Give your answer as a decimal (to at least 3 places) or fraction Submit QuestionQuestion 5Unattempted Question 6Check0/5 ptsRetries4Reattempts3InfoDetails

Ages	Number of students
15-18	3
19-22	5
23-26	4
27-30	2
31-34	8
35-38	6

Based on the frequency distribution above, find the relative frequency for the class 15-18 .

Relative Frequency = % Give your answer as a percent, rounded to one decimal place

Submit QuestionQuestion 6Unattempted Question 7Check0/5 ptsRetries4Reattempts3InfoDetailsFor the data shown, answer the questions. Round to 2 decimal places.

x

15.6

24.3

19.6

24.4

9

10

3.4

Find the mean: Find the median: Find the standard deviation: Submit QuestionQuestion 7Unattempted Question 8Check0/5 ptsRetries4Reattempts3InfoDetailsA binomial experiment consists of 14 trials. The probability of success on trial 7 is 0.86. What is the probability of failure on trial 11?

• 0.14
• 0.77
• 0.31
• 0.74
• 0.81
• 0.89

Submit QuestionQuestion 8Unattempted Question 9Check0/5 ptsRetries4Reattempts3InfoDetailsMatching questions ask you to match each question on the left with one of the choices on the right. Not all choices on the right will necessarily be used. Enter a letter (a,b,c,etc) from the right into each of the boxes on the left.

• -abcd Uniform
• -abcd Binomial
• -abcd Poisson
• -abcd Exponential

1. a constant probability density and charts as a rectangle
2. fixed number of trials with only 2 possible outcomes and the trials are independent
3. models the time until some specifi event occurs such as equipment failure
4. events happen with a known average rate and independently of the time since the last event

Submit QuestionQuestion 9Unattempted Question 10Check0/5 ptsRetries4Reattempts3InfoDetails

Give an example from daily life that shows a binomial distribution and explain why it is binomial.

Submit QuestionQuestion 10Unattempted Question 11Check0/5 ptsRetries4Reattempts3InfoDetails

Many electronics follow a failure rate described by an exponential probability density function (PDF). Solar panels are advertised to last 20 years or longer, but panels made in China are failing at a higher rate. The time-to-failure of this device is usually exponentially distributed with mean 6 years. What is the probability of failure in the first 6 years?

Submit QuestionQuestion 11Unattempted Question 12Check0/5 ptsRetries4Reattempts3InfoDetails

Hint 1

Why is the probability that a continuous random variable equals a specific number zero? That is, why is P(X=b)=0 for any number b?

Submit QuestionQuestion 12Unattempted Question 13Check0/5 ptsRetries4Reattempts3InfoDetailsAdult men have heights with a mean of 69.0 inches and a standard deviation of 2.8 inches. Find the z-score of a man 74.2 inches tall. (to 2 decimal places)Submit QuestionQuestion 13Unattempted Question 14Check0/5 ptsRetries4Reattempts3InfoDetailsThe physical plant at the main campus of a large state university recieves daily requests to replace florecent lightbulbs. The distribution of the number of daily requests is bell-shaped and has a mean of 39 and a standard deviation of 7. Using the 68-95-99.7 rule, what is the approximate percentage of lightbulb replacement requests numbering between 39 and 53? Do not enter the percent symbol. ans = %Submit QuestionQuestion 14Unattempted Question 15Check0/5 ptsRetries4Reattempts3InfoDetailsAssume that the readings at freezing on a batch of thermometers are normally distributed with a mean of 0C and a standard deviation of 1.00C. A single thermometer is randomly selected and tested. FindP₇₄, the 74-percentile. This is the temperature reading separating the bottom 74% from the top 26%. P₇₄= CSubmit QuestionQuestion 15Unattempted Question 16Check0/5 ptsRetries4Reattempts3InfoDetails

Explain the Central Limit Theorem and the Law of Large Numbers. There are 3 key points. Include the formula for the standard error.

Submit QuestionQuestion 16Unattempted Question 17Check0/5 ptsRetries4Reattempts3InfoDetails

The stock market jumped 1% today. Lending Tree, a peer-to-peer lender, has a average daily range of 5.5%. Are these large movements and how do we tell?

Submit QuestionQuestion 17

Examine the following survey question for any sources of bias. Given humanity's great tradition of exploration, do you favor continued funding for space flights? Is the question biased?

• Yes
• No

Submit QuestionQuestion 1Unattempted Question 2Check0/5 ptsRetries4Reattempts3InfoDetailsThe histogram below shows the distances (in meters) of all qualifying throws for the men's discus event at the 2004 Summer Olympics. Which of the following terms apply to this histogram? (Select all that apply.)

• symmetric
• negatively skewed
• bimodal
• uniform
• unimodal
• positively skewed

Which measure of center is most appropriate for this data?

• mean
• median

Which measure of spread is most appropriate for this data?

• range
• IQR
• standard deviation

Submit QuestionQuestion 2Unattempted Question 3Check0/5 ptsRetries4Reattempts3InfoDetails

What are two important first steps in data analysis?

• Cleaning the data and exploring it
• Cleaning and scrubbing the data
• the box plot and the 5 number summary
• correlation and regression

Submit QuestionQuestion 3Unattempted Question 4Check0/5 ptsRetries4Reattempts3InfoDetailsWhich of the following statements isfalse?

• Two independent events cannot occur at the same time.
• Two complementary events cannot occur at the same time.
• Two disjoint events cannot occur at the same time.

Submit QuestionQuestion 4Unattempted Question 5Check0/5 ptsRetries4Reattempts3InfoDetailsSuppose that 31% of people own dogs. If you pick two people at random, what is the probability that they both own a dog? Give your answer as a decimal (to at least 3 places) or fraction Submit QuestionQuestion 5Unattempted Question 6Check0/5 ptsRetries4Reattempts3InfoDetails

Ages	Number of students
15-18	3
19-22	5
23-26	4
27-30	2
31-34	8
35-38	6

Based on the frequency distribution above, find the relative frequency for the class 15-18 .

Relative Frequency = % Give your answer as a percent, rounded to one decimal place

Submit QuestionQuestion 6Unattempted Question 7Check0/5 ptsRetries4Reattempts3InfoDetailsFor the data shown, answer the questions. Round to 2 decimal places.

x

15.6

24.3

19.6

24.4

9

10

3.4

Find the mean: Find the median: Find the standard deviation: Submit QuestionQuestion 7Unattempted Question 8Check0/5 ptsRetries4Reattempts3InfoDetailsA binomial experiment consists of 14 trials. The probability of success on trial 7 is 0.86. What is the probability of failure on trial 11?

• 0.14
• 0.77
• 0.31
• 0.74
• 0.81
• 0.89

Submit QuestionQuestion 8Unattempted Question 9Check0/5 ptsRetries4Reattempts3InfoDetailsMatching questions ask you to match each question on the left with one of the choices on the right. Not all choices on the right will necessarily be used. Enter a letter (a,b,c,etc) from the right into each of the boxes on the left.

• -abcd Uniform
• -abcd Binomial
• -abcd Poisson
• -abcd Exponential

1. a constant probability density and charts as a rectangle
2. fixed number of trials with only 2 possible outcomes and the trials are independent
3. models the time until some specifi event occurs such as equipment failure
4. events happen with a known average rate and independently of the time since the last event

Submit QuestionQuestion 9Unattempted Question 10Check0/5 ptsRetries4Reattempts3InfoDetails

Give an example from daily life that shows a binomial distribution and explain why it is binomial.

Submit QuestionQuestion 10Unattempted Question 11Check0/5 ptsRetries4Reattempts3InfoDetails

Many electronics follow a failure rate described by an exponential probability density function (PDF). Solar panels are advertised to last 20 years or longer, but panels made in China are failing at a higher rate. The time-to-failure of this device is usually exponentially distributed with mean 6 years. What is the probability of failure in the first 6 years?

Submit QuestionQuestion 11Unattempted Question 12Check0/5 ptsRetries4Reattempts3InfoDetails

Hint 1

Why is the probability that a continuous random variable equals a specific number zero? That is, why is P(X=b)=0 for any number b?

Submit QuestionQuestion 12Unattempted Question 13Check0/5 ptsRetries4Reattempts3InfoDetailsAdult men have heights with a mean of 69.0 inches and a standard deviation of 2.8 inches. Find the z-score of a man 74.2 inches tall. (to 2 decimal places)Submit QuestionQuestion 13Unattempted Question 14Check0/5 ptsRetries4Reattempts3InfoDetailsThe physical plant at the main campus of a large state university recieves daily requests to replace florecent lightbulbs. The distribution of the number of daily requests is bell-shaped and has a mean of 39 and a standard deviation of 7. Using the 68-95-99.7 rule, what is the approximate percentage of lightbulb replacement requests numbering between 39 and 53? Do not enter the percent symbol. ans = %Submit QuestionQuestion 14Unattempted Question 15Check0/5 ptsRetries4Reattempts3InfoDetailsAssume that the readings at freezing on a batch of thermometers are normally distributed with a mean of 0C and a standard deviation of 1.00C. A single thermometer is randomly selected and tested. FindP₇₄, the 74-percentile. This is the temperature reading separating the bottom 74% from the top 26%. P₇₄= CSubmit QuestionQuestion 15Unattempted Question 16Check0/5 ptsRetries4Reattempts3InfoDetails

Explain the Central Limit Theorem and the Law of Large Numbers. There are 3 key points. Include the formula for the standard error.

Submit QuestionQuestion 16Unattempted Question 17Check0/5 ptsRetries4Reattempts3InfoDetails

The stock market jumped 1% today. Lending Tree, a peer-to-peer lender, has a average daily range of 5.5%. Are these large movements and how do we tell?

Submit QuestionQuestion 17