Statistics
For a normal population with a mean of 10 and a variance 4, the
P(
X ≥ 10) is ___.
P(
X ≥ 10) is ___.
If the random variable of x is normally distributed, ____ % of all possible observed values of x will be within two standard deviations of the mean.
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If the scores on an aptitude test are normally distributed with mean 500 and standard deviation 100, what proportion of the test scores are less than 585?
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What is the probability that a random variable having a standard normal distribution is between .87 and 1.28?
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The flying time of a drone airplane has a normal distribution with mean 4.76 hours and standard deviation of .04 hours. What is the probability that the drone will fly:
Less than 4.66 hours?
Less than 4.66 hours?
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The flying time of a drone airplane has a normal distribution with mean 4.76 hours and standard deviation of .04 hours. What is the probability that the drone will fly:
Between 4.70 and 4.82 hours?
Between 4.70 and 4.82 hours?
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The weight of a product is normally distributed with a mean of four ounces and a variance of .25 “squared ounces.” What is the probability that a randomly selected unit from a recently manufactured batch weighs no more than 3.5 ounces?
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The weight of a product is normally distributed with a mean of four ounces and a variance of .25 “squared ounces.” What is the probability that a randomly selected unit from a recently manufactured batch weighs more than 3.75 ounces?
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(Percentile) During the past six months, 73.2% of US households purchased sugar. Assume that these expenditures are approximately normally distributed with a mean of $8.22 and a standard deviation of $1.10. 99% of the households spent less than what amount?
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(Percentile) During the past six months, 73.2% of US households purchased sugar. Assume that these expenditures are approximately normally distributed with a mean of $8.22 and a standard deviation of $1.10. 80% of the households spent more than what amount?
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(Percentile) Suppose that the waiting time for a license plate renewal at a local office of a state motor vehicle department has been found to be
normally distributed with a mean of 30 minutes and a standard deviation of 8 minutes. Complete the following statement: Only 20% of the individuals wait less than _____ minutes.
normally distributed with a mean of 30 minutes and a standard deviation of 8 minutes. Complete the following statement: Only 20% of the individuals wait less than _____ minutes.
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(Percentile) Suppose that the waiting time for a license plate renewal at a local office of a state motor vehicle department has been found to be
normally distributed with a mean of 30 minutes and a standard deviation of 8 minutes. Suppose that in an effort to provide better service to the public, the director of the local office is permitted to provide discounts to those individuals whose waiting time exceeds a predetermined time. The director decides that 15% of the customers should receive this discount. What are the numbers of minutes they need to wait to receive the discount?
normally distributed with a mean of 30 minutes and a standard deviation of 8 minutes. Suppose that in an effort to provide better service to the public, the director of the local office is permitted to provide discounts to those individuals whose waiting time exceeds a predetermined time. The director decides that 15% of the customers should receive this discount. What are the numbers of minutes they need to wait to receive the discount?
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Percentile) A set of final examination grades in a calculus course was found to be normally distributed with a mean of 69 and a standard deviation of 9.
Only 5% of the students taking the test scored higher than what grade?
Only 5% of the students taking the test scored higher than what grade?
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(Percentile) The yearly cost of dental claims for the employees of the local shoe manufacturing company is normally distributed with a mean of $105 and a standard deviation of $35. What is the yearly cost at which 35% of the employees fall at or below?
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A plant manager knows that the number of boxes of supplies received weekly is normally distributed with a mean of 200 and a standard deviation of 20. What percentage of the time will the number of boxes received weekly be between 180 and 210?
$1 FOR EVERY CORRECT ANSWER
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