If the average of a random variable is 95 and the standard deviation is 20 then the proportion of observations between 35 and 155 is at least

Q: A team of engineers developed a device that measures the distance of a ship from the shore. The…

A: Let X be the Continuous random variable of distance of a ship from the store follows Normal…

Q: The mean yearly rainfall in Sydney, Australia, is about 137 mm and the standard deviation is about…

A: From the provided information, Mean (µ) = 137 mm Standard deviation (σ) = 69 mm

Q: A random sample of 25 observations yield a mean of 116 and a standard deviation of 12. What is the…

A: Given data,Mean μ=116sd σ=12P(X>1150)=?

Q: If a sample has a mean of 100 and a standard deviation of 6, what is the value in the data set that…

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Q: The speeds of all cars on the tollway was found to be normally distributed with a mean of 63 miles…

A: It is given that that µ=63 mile per hour. Obtain the standard deviation of the speeds of all cars:

Q: The distribution of scores for the third exam in a statistics course has a mean of 74 and a standard…

A: Given Information: Mean, μ=74 Standard Deviation, σ=15 Sample Size, n=36

Q: In 1999, the murder rates (per 100000) for the 50 states and the District of Columbia had a mean of…

A: Given mean is 5.9 and standard deviation 6.3 sample size is 5

Q: population has a mean of 350 and a standard deviation of 25, determine the probability that a random…

A: GIVEN DATA, μ=350σ=25n=40p(335<x¯<375)=?

Q: An educational study to be conducted requires a test score in the middle 40% range. If the mean is…

A: Let us assume X=score Given that X follows a normal distribution with mean= 100 and standard…

Q: A simple random sample of 36 observations was taken from a large population. The sample mean and the…

A: The sample mean and the standard deviation are μ = 80 and σ = 12 respectively.Let X denotes the…

Q: If the average of a random variable is 83 and the standard deviation is 18 then the proportion of…

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Q: Suppose that the scores on a reading ability test are normally distributed with a mean of  60  and…

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Q: If on an average 8 ships out of 10 arrive safely at a port, find the mean and standard deviation of…

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Q: Fran is training for her first marathon, and she wants to know if there is a significant difference…

A: Denote μ1, μ2 as the population means number of miles run each week by group runners and individual…

Q: In 1999, the murder rates (per 100,000) for the 50 states and the District of Columbia had a mean of…

A:

Q: According to the Bureau of Labor Statistics, the average number of weeks an individual is unemployed…

A: The Z-score of a random variable X is defined as follows: Z = (X – µ)/σ. Here, µ and σ are the mean…

Q: If the mean exam score of a class was 75%, with a standard deviation of 15%,what percent of students…

A: Given,mean(μ)=0.75standard deviation(σ)=0.15

Q: What proportion of the students scored lower than 80 if the distribution of these grades can be…

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Q: According to the American Red Cross, 11.6% of all Connecticut residents have Type B blood. A random…

A: The question is about discrete probability distributionGiven :Probability of all CT residents have…

Q: Suppose the average credit card debt for Americans is $7000 and is not normally distributed with a…

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Q: Can the standard deviation of a data set be zero

A: Standard deviation can not be negative.

Q: A random sample of 25 observations yield a mean of 106 and a standard deviation of 12. What is the…

A: It is given that mean and standard deviation are106 and 12, respectively.By using central limit…

Q: The average drive to work is 9.6 miles. Assume the standard deviation is 1.8 miles. If a random…

A: From the given information, x¯=9.6σ=1.8n=36

Q: If only the upper 30% of a normally distributed class passed a quiz for which the mean was 70 and…

A: According to the given information in this question we need to find the lowest score a student could…

Q: If a population has a standard deviation σ , then the standard deviation of the mean of 100 randomly…

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Q: Americans spend an average 12.2 minutes in the shower. If the standard deviation of the variable is…

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Q: a survey found that 21% of Americans watch fireworks on television on July 4.  Find the mean,…

A: According to the given question, a survey found that 21% of Americans watch fireworks on television…

Q: A simple random sample of 36 observations was taken from a large population. The sample mean and the…

A:

Q: Suppose that in the population of all healthy humans, body temperature follows a normal distribution…

A: according to central limit theorem if sample size is large enough, then sampling distribution of…

Q: Furnace repair bills are normally distributed with a mean of 267 dollars and a standard deviation of…

A: Let us denote: X=Furnace repair billsGiven that X follows a normal distribution with mean=267 and…

Q: Furnace repair bills are normally distributed with a mean of 269 dollars and a standard deviation of…

A: Given: Population meanμ=269Sample size(n) =64Population standard deviationσ=20 Consider X be the…

Q: 5 will be drawn from a population of test takers with a mean of 150 and standard deviation 9. Find…

A: Given that  Sample size (n) = 75 Population mean (μ) = 150 Standard deviation (σ) = 9   We know that…

Q: A random sample of 18 light bulbs is drawn from a normally distributed population. The population…

A: Since, the samples are drawn from the normal population thus sampling distribution of sample mean…

Q: According to a study of TV viewing habits, the average number of hours an American over the age of 2…

A: Given data,Standard deviation is σ=16If n=64 standard error of the mean(σx)=?

Q: If a sample size is 100 and the population standard deviation is 30 then the standard deviation of…

A: Given: Sample size (n) = 100 population standard deviation =30