1) When referring to the normal probability distribution, there is not just one; there is a “family” of distributions.
2) The standard normal probability distribution is unique because it has:
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Choose one:
Any mean and a standard deviation of 1
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-A mean of 0 and any standard deviation
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-A mean of 0 and a standard deviation of 1
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-A mean of 1 and any standard deviation
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3) Tables of normal distribution probabilities are found in many statistics books. These probabilities are calculated from a normal distribution with. Choose one:
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a mean of 100 and a standard deviation of 15
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a mean of 1 and a standard deviation of 1
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a mean of 0 and a standard deviation of 1
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a mean of 0 and a standard deviation of 15
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4) What is the percentage of the total area under the normal curve within plus and minus two standard deviations of the mean? Choose one:
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34.13%
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68.26%
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99.74%
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95.44%
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5) The time to fly between New York City and Chicago is uniformly distributed with a minimum of 120 minutes and a maximum of 150 minutes. What is the probability that a flight is between 125 and 140 minutes? Choose one:
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1.00
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0.333 minutes
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0.5
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10 minutes
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6) If an average of 12 customers are served per hour, then one customer arrives every. Choose one.
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5 minutes
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10 minutes
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60 minutes
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12 minutes
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7) In a uniform probability distribution, P(x) is constant between the distribution’s minimum and maximum values.
8) The total area of a normal probability distribution is. Choose one:
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-approximated by the binomial distribution.
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-1.00.
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-dependent on a value of ‘z’.
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-between -3.0 and 3.0.
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9) The shape of any uniform probability distribution is. Choose one:
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-Positively skewed
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-Rectangular
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-Negatively skewed
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-Bell shaped
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10) The time to fly between New York City and Chicago is uniformly distributed with a minimum of 120 minutes and a maximum of 150 minutes. What is the mean? Choose one:
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-150 minutes
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-120 minutes
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-270 minutes
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-135 minutes
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11) For the exponential distribution, the mean and standard deviation are equal.
12) Some normal probability distributions have equal arithmetic means, but their standard deviations may be different.
13) A random variable from an experiment where outcomes are normally distributed. Choose one:
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-can have a mean of 0 and a standard deviation of 1.
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-can have only a few discrete values.
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-can have no values.
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-can have any value between – ∞ and + ∞.
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14) If an average of 60 customers are served per hour, then one customer arrives every. Choose one:
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-1 minute
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-12 minutes
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-60 minutes
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-10 minutes
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15) What is a normal distribution with a mean of 0 and a standard deviation of 1 called? Choose one:
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-Binomial probability distribution
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-Standard normal distribution
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-Frequency distribution
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-Z-score
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16) A binomial distribution has 50 trials (n = 50) with a probability of success of 0.50 (π=0.50). To use the normal distribution to approximate the binomial, what are the mean and standard deviation? Choose one?
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µ =25 and σ = 4.33
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µ =25 and σ = 12.5
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µ = 25 and σ = 3.5355
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µ =50 and σ = 100
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17) In an illustration of a normal probability distribution, a shaded area represents. Choose one:
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-a probability
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-a combination
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-a standard deviation
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-a permutation
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18) Two normal distributions are compared. One has a mean of 10 and a standard deviation of 10. The second normal distribution has a mean of 10 and a standard deviation of 2. Which of the following is true?
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-The distributions are from two different families of distributions
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-The dispersions of the distributions are different
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-The dispersions of the distributions are the same
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-The locations of the distributions are different
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19) The area under the normal curve within plus and minus one standard deviation of the mean is about 68.26%.
20) The standard deviation of any uniform probability distribution is. Choose one of the following:
