An economist would like to estimate the mean amount of money that a family spends to within $82. If the amount spent by a family is considered to be normally distributed with a standard deviation of $490, what sample size would be necessary to be 96% confident?

Q: A pharmaceutical company claims that a drug is effective in treating 90% of people having severe…

A: Given that,The random variable follows binomial distribution,n=6p=90%=0.9,q=1-p, q= 0.1

Q: A health care prifessional wishes to estimate the birth weights of infants. How large a sample must…

A: Given Information :  A health care professional wishes to estimate the birth weights of infants. He…

Q: If the variance of the recorded weights of nine basketball players is 2.36, what is the value of the…

A:

Q: Suppose the exam average in a class is 82% with a standard deviation of 6. What proportion of…

A:

Q: Dr. Samwell Tarly wants to estimate the number of books checked out of the library in the past year.…

A: It is given that the mean is 10,000 and the standard deviation is 10.

Q: what if the standard deviation was 30, instead of 60

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Q: a) Describe carefully how mean deviation, standard deviation and quartile deviatinn of any given…

A: Given: The provided terms are: 1) Mean Deviation. 2) Standard deviation. 3) Quartile deviation. The…

Q: According to a recent survey, the population distribution of number of years of  education for…

A: What is the standard error of mean?

Q: The mean of a population (μ) is 120 and the standard deviation is 20.  What is the mean of the…

A: From the provided information, Mean (µ) = 120 Standard deviation (σ) = 20

Q: An advertising agency has stated that 20% of all television viewers watch a particular program. How…

A: From the provided information, An advertising agency has stated that 20% of all television viewers…

Q: Suppose you found that the average sea- faring bird can fly 8,000 km without stopping. The wandering…

A:

Q: A successful basketball player has a height of 6 feet 8 ​inches, or 203 cm. Based on statistics from…

A: Consider X is a random variable defined as the height of a successful basketball player.The provided…

Q: Assuming that the heights of college women are normally distributed with mean 62 inches and standard…

A:

Q: If the height of 1000 students in a University Campus closely follows a normal distribution with a…

A:

Q: video game c

A: given, sample size(n) = 1500 sample mean (x̄) = 115 sample stadard deviation (s) = 11

Q: If a distribution has a mean of 50 and a standard deviation of 5, what value would be -1 standard…

A: Given, μ=50σ=5z=-1x=?

Q: If the average number of textbooks in professors' offices is 14, the standard deviation is 5, and…

A: Given that For textbooks, mean = 14, and SD = 5 For age, mean = 42, and SD = 10

Q: What is the sum of the deviation scores for the data in the frequency distribution table below?

A: Sum of deviation  of scores from mean is always zero.

Q: A recent Gallop Poll indicates that 80 % of voting age adults disapprove of Congress. If 700 voting…

A: Let p be the probability that a voting age adult disapproves of Congress. Given that p = 0.80 Let X…

Q: If the range of a data set is 56, find the approximate value of the standard deviation, using the…

A:

Q: If a set of grades for a class has a large range and a small standard deviation, what can you say…

A: It is given that a set of grades for a class has large range and a small standard deviation.

Q: An advertising executive wants to estimate the mean amount of time that consumers spend with digital…

A: a) The sample size is 117 and it is obtained below: From the given information, the population…

Q: Suppose the exam average in a class is 48% with a standard deviation of 15. What proportion of…

A:

Q: In a survey of a group of men, the heights in the 20-29 age group were normally distributed, with a…

A: To determine: To determine how may would you expect to be taller than 71 inches . Given data: In a…

Q: In Melanie's Styling Salon, the time to complete a simple haircut is normally distributed with a…

A: Given, Mean = μ =25SD = σ =4

Q: The population standard deviation for the height of high school basketball players is three inches.…

A: Solution: 6. From the given information, confidence level is 0.95, σ=3 inches and E=1.

Q: In general, the larger the animal the longer the length of pregnancy. For the horse, for example,…

A: A z-score represents the position of a data point in terms of its distance from the mean when…

Q: If research samples 28 college students and wants to compare the sample mean of 8 to the population…

A: From the provided information, Sample size (n) = 28 Sample mean (x̄) = 8 Population mean (µ) = 12…

Q: A company pays their employees an average of $52,500 per year. If the standard deviation for the…

A: Given : A company pays their employees an average of $52,500 per year. If the standard deviation for…

Q: For a distribution with a mean of 70, if the distribution had a standard deviation of 4, would a…

A: the PDF of normal distribution is = 1/σ * √2π * e ^ -(x-u)^2/ 2σ^2standard normal distribution is a…

Q: If the average salary of a computer programmer is $71, 800 with a standard deviation of 13, 000,…

A: I am attaching image so that you understand each and every step.

Q: he History test had a national mean of µ = 52 and a standard deviation of  σ= 9. How much sampling…

A: Given data, µ = 52  σ= 9 n=27 sampling error=?

Q: Suppose the test scores in a class are normally distributed with a mean of 70 and a standard…

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: The students of a large university in Luzon were studied regarding their hours of sleep at night.…

A: As the distribution of the hours of sleep can be modeled as normal distribution with mean μ of 6.9…

Q: When a distribution is bell-shaped, approximately what percentage of data values fall within 1…

A: We know that, the empirical rule which is also known as 68-95-99.7 rule.  The Empirical Rule finds…

Q: suppose the heights of 18-year-old men are approximately normally distributed, with mean 73 inches…

A:

Q: Describe  the scores in a sample  that has a standard  deviation of zero

A: If the standard deviation is zero there will be no dispersion of scores from the Mean. It means that…

Q: according to police sources, a car with a certain protection system will be recovered 90% of the…

A: Given problem is a binomial distribution with:

Q: 3.5 inches, how tall does a woman have to be to have a height in the 90th percentile? Round off to 1…

A: Given : Population Mean,μ = 65.0 Population Standard Deviation,σ = 3.5

Q: The variance of a sample of 81 observations equals 64. what is  standard deviation of the sample ?

A: Given data ,no of samples n=81Variance σ2=64Std. deviation σ= ?

Q: As reported in Runner's World magazine, the times of the finishers in the New York City 10- km run…

A: Percentile : Percentile is the number such that certain percentage of the fall below that values.…

Q: The standard deviation of the distribution of sample means would be equal to:

A: The standard deviation of the distribution of sample means would be equal to ?

Q: A biologist found the wingspans of a group of monarch butterflies to be normally distributed, with a…

A: Given,Mean (μ) = 52.2Standard deviation (σ) = 2.3a) Required probability is…

Q: In an all boys school, the heights of the student body are normally distributed with a mean of 71…

A:

Q: According to the Department of Education the mean number of hours college students spend studying…

A:

Q: If the coefficient of variation for a data is given as  35%, and the standard deviation for the same…

A: Given that Coefficient of variation, C.V =  35% And the standard deviation is SD = 32

Q: If a normally distributed group of test scores have a mean of 70 and a standard deviation of 12,…

A: It is given that the mean is 70 and the standard deviation is 12.

Q: A researcher in Des Moines, Iowa sampled 56 households and found the mean number of puppies per…

A: # sample size n=56  population mean mu=3.03  standard deviations=1.5  then to find 62nd percentile…