For a sample, a score that is 12 points above the mean has a z-score of z = 1.20. What is the sample standard deviation?

Q: The scores on the board are Normally distributed with a mean of 67 and a standard deviation of 13.…

A: From the provided information,X~N (67, 13)The bottom 5% of students will fail.

Q: Why is the standard deviation preferable to the range as a measure of variation?

A: A range is the most common and easily understandable measure of dispersion. It is the difference…

Q: an exam score has a mean of 506 and a standard deviation of 100. What exam score corresponds to a…

A: μ  = 506 , σ = 100  Z~ N(0,1)

Q: Salaries for teachers in a particular elementary school district are normally distributed with a…

A: The properties of the normal distribution is,   The Normal distribution curve is and bell shaped…

Q: When IQ scores are normally distributed with a mean of 100 and a standard deviation of 15. What is…

A:

Q: On a recent quiz, the class mean of 74 with the standard deviation of 3.9.  calculate the z-score…

A: Given data  μ = 74σ = 3.9x1 = 95x2 = 70

Q: Suppose that the weights of candy bars vary according to a normal distribution, with mean of 62…

A: The question is about normal dist. Given : The mean weights of candy bars ( μ ) = 62 g The std.…

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

A:

Q: The ages of the members of a popular ski club is normally distributed with a mean of 46 years and a…

A: Given that the ages of the members of a popular ski club is normally distributed with a mean of 46…

Q: Assume that adults have IQ scores that are normally distributed with a mean of 99.2 and a standard…

A: Given info: IQ scores are normally distributed with a mean of μ=99.2 and a standard deviation…

Q: The Stanford-Binet IQ test is scaled so that scores have a mean of 100 and a standard deviation of…

A: Let "X" be the Stanford-Binet IQ test

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: if a student scored 88 points on a test when the mean score was 80.2 and the standard deviation was…

A: From the provided information, Mean (µ) = 80.2 Standard deviation (σ) = 5.7

Q: The mean annual income for people in a certain city (in thousands of dollars) is 42, with a standard…

A: The formula for mean of the Z-score is, Z=x¯-μσn Here n is the sample size, μ is the population mean…

Q: A dataset has a mean of 48.1 and a standard deviation of 6.3. What is the z-score of the value 18.5,…

A: Solution  Given That, A dataset has a mean of 48.1 and a standard deviation of 6.3. What is the…

Q: Assume that women have heights that are normally distributed with a mean of 63.6 inches and a…

A:

Q: Hogie lizards have tail lengths that are normally distributed with a mean of 22.5 cm and a standard…

A:

Q: What is the corresponding Z score ? Mean is 70, standard deviation is 10 and X= 89

A: We have to find z score.

Q: In a standardized exam the mean score is 400 with a standard deviation of 50. Assume the scores…

A: Solution

Q: Assume that adults have IQ scores that are normally distributed with a mean of 104.6 and a standard…

A:

Q: Assume that the average length of some wire is 52 inches with a standard deviation of 6.5 inches. At…

A: Given: The average length of the wire, μ=52 Standard deviation, σ=6.5 We need to determine at most…

Q: A standardized test has a pop. mean of 152 and a standard deviation of 16. Molly scores at the 91st…

A:

Q: 2000 freshmen at state university took a biology test. the scores were normally distributed with a…

A: Solution: Let X be the scores. From the given information, X follows normal distribution with mean…

Q: A police recruit received a score of 70 on an indurance test for which the mean score is 65.5. The…

A: We know that the If μ is the mean score and σ is the standard deviation for this set of test scores,…

Q: an exam score has a mean of 506 and a standard deviation of 100. What exam score corresponds to a…

A:

Q: ly normal and has a standard deviation of 88% of students scored above a 800. What is the mean of

A: The mean of the binomial random variable obtained by the formula μ=np, where (n) is the number of…

Q: For a social club, the members had a mean age of 68 and a standard deviation of 10 years.  What is…

A: The mean is 68 and the standard deviation is 10.

Q: Sally had a z score of +0.25 on a test with a mean of 62 and a standard deviation of 5. What was her…

A: From the provided information,Z score = +0.25

Q: what is the value of the standard deviation of the weekly earnings of the bus drivers?

A: Let X be the random variable for the weekly earnings of bus drivers.Given that,Population mean

Q: Give the mean and the standard deviation of the distribution of means for mean=100; Variance=100;…

A:

Q: Assume that adults have IQ scores that are normally distributed with a mean of 95.4 and a standard…

A: Let "X" be the IQ score of adults. Draw the normal curve and shade the area of 0.25 to the left…

Q: Assume that adults have IQ scores that are normally distributed with a mean of 95.6 and a standard…

A: Given: x~N(μ,σ)μ=95.6σ=24.3

Q: The Psych 230 students finished the course with a total population mean of 130 points and the…

A:

Q: Assume that adults have IQ scores that are normally distributed with a mean of 100.3 and a standard…

A: Assume that adults have IQ scores that are normally distributed with a mean of 100.3 and a standard…

Q: A test score of 36 has an equivalent standard score (z-score) of -2.4. If the standard deviation is…

A:

Q: Q3 :- :- if you know the standard deviation = 3 for measured data, what is the variance ?

A: Given in question  Standard deviation = 3

Q: The playing life of a Sunshine radio has a Normal distribution with a mean of 600 hours and a…

A: The playing life of a radio is normally distributed with mean 600 hours and standard deviation of…

Q: Assume that an intelligence test scores are distributed normallt with a mean of 100 and a standard…

A: Standard normal distribution: The standard normal distribution is a special case of normal…

Q: A normal distribution has a mean of 3.7 and a standard deviation of 2.3. What is the median?

A: From the provided information,

Q: We have a distribution with a mean of ? = 35 and ? = 3.5. Find the raw score equivalents for the…

A:

Q: Assume that adults have iq scores that are normally distributed with a mean of 98.2 and a standard…

A:

Confidence Intervals

When we calculate intervals in probability and statistics, it can be simply termed as finding out a confidence interval. The confidence interval is usually calculated from the data set which is observed. The value of the parameter that needs to be calculated is present here only.