Distributions Statistics

The mean temperature in Glens Falls for the month of February is 23 degrees with a standard deviation of 4.2 degrees. Approximately what percent of days in February will be between 14.6 and 31.4 degrees?

• 68%

• 50%

• 99.7%

• 95%

• Yes, because all of the probabilities are between 0 and 1 inclusive and the sum of all the probabilities is 1.
• No, all probabilities are not be between 0 and 1 inclusive
• No, the sum of all the probabilities is not 1.
• Yes, because the distribution is symmetric

• Yes, because all of the probabilities are between 0 and 1 inclusive and the sum of all the probabilities is 1.
• No, all probabilities are not be between 0 and 1 inclusive
• No, the sum of all the probabilities is not 1.
• Yes, because the distribution is symmetric

• Mean =7.92
  Variance =  2.6928
  Standard Deviation = 1.64
• Mean = 12 
  Variance = .66
  Standard Deviation = .44
• Mean = 12
  Variance = 7.92
  Standard Deviation = 2.814
• Mean =7.92
  Variance = 1.64
  Standard Deviation = 2.6928 

How is the data distributed in this histogram?

• Symmetrically

• Skewed Right

• Skewed Left

The following table represents the probability distribution X, the employment status of adults in a city. What is the probability that the adults isn't retired?

The following table represents the probability distribution X, the employment status of adults in a city.

What is the probability that the adults isn't retired?

• Mean = 5.5 
  Variance =  1.57
  Standard Deviation = 2.475
• Mean = 5.0 
  Variance = 5.5
  Standard Deviation = 2.345
• Mean = 10
  Variance = .55
  Standard Deviation = .45
• Mean = 5.5 
  Variance = 2.475 
  Standard Deviation = 1.57 

A company states that 2% of its computers are returned for defects.  We take a sample of 100 computers to find the probability of 10 being defective.  Is this a binomial distribution?

• No because there is not a fixed number of trials.

• No because their are more than 2 outcomes.

• Yes since there are a fixed number of independent trials, outcomes in 2 categories, and the probability of defect is constant.

• No since computers would not be independent.

The table represents the probability of guessing correct on a 5 question true-false quiz.  Find the probability for at least 4 questions correct.

• .03125

• .15625

• .3125

• .1875