- A card is drawn, with replacement, from a regular deck of cards 16 times. Let random variable X represent number of clubs among those 16 cards selected (there are 13 clubs in every deck; there are 52 cards in a deck). Find the variance of X,
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The length of life of an instrument produced by a machine has a normal distribution with a mean of 12 months and standard deviation of 2 months. Find the probability that an instrument produced by this machine will last less than 7 months.Round to the nearest thousandth.
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The length of life of an instrument produced by a machine has a normal distribution with a mean of 12 months and standard deviation of 2 months.Find the probability that an instrument produced by this machine will last between 7 and 12 months. Round to the nearest thousandth.
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The length of life of an instrument produced by a machine has a normal distribution with a mean of 12 months and standard deviation of 2 months. Find how long an instrument that separates the bottom 83.398% will last? Round to the nearest hundredth.
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The length of life of an instrument produced by a machine has a normal distribution with a mean of 12 months and standard deviation of 2 months. What is the probability that the average number of months that these 100 instruments will last is greater than 12.2 months? Round to the nearest thousandth.
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A die is rolled 360 times. If you want to use normal approximation to find the probability that the number of 4 was rolled at least 100 times,what is the mean of the normal distribution that you would use in this case.
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A die is rolled 180 times. If you want to use normal approximation to find the probability that the number of 4 was rolled at least 20 times,what is the standard deviation of the normal distribution that you would use in this case
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A die is rolled 360 times. Let say that you want to use normal approximation to find the probability that the number of 4 was rolled less than 100 times. You need to find the probability that X<100. Explain how you would use continuity correction in this case.
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A die is rolled 360 times. Let say that you want to use normal approximation to find the probability that the number of 4 was rolled exactly 100 times. You need to find the probability that X=100. Explain how you would use continuity correction in this case.
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What is the name of the theorem that states that the sampling distribution of the sample mean is approximately normal when the sample is large?
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Determine whether the following random variables have a binomial distribution:
A) Ten students are chosen from a statistics class (with replacement) of 400 students. Let X be the number of students who passed the class.
B) A die is tossed three times. Let X be the sum of the three numbers obtained.
C) A coin is tossed until a head appears. Let X be the number of tosses.
only A is a binomial distribution
only B is a binomial distribution
only C is a binomial distribution
only A and B is a binomial distribution
only A and C is a binomial distribution
only B and C is a binomial distribution
all A, B, and C are binomial distributions
none is a binomial
