160 Answered Questions for the topic Standard Deviation
Data Management Probability, Standard Deviation, and Normal Distribution Question:
Hi, how would i get started on solving this question? The average monthly rainfall in Southern California is 26 mm. If rainfall data over the year is normally distributed with a standard deviation... more
Standard Deviation Mean
Mean of Test scores
the mean of normal distributed test score is 79 and the standard deviation is 5 if there are 242 test scores in the data sample how many of them were in the 84 to 94 range
STATS IN PSYCHOLOGY
Assume your class took a final exam in psychology in which the scores produced a normal curve with a mean score of 80 and a standard deviation of 5. If the student scores within two standard... more
Statistics with confidence intervals
A random sample of 80 college students was asked, “How many hours do you study each week?” After gathering the data, the sample has a mean of 14 hours and a standard deviation of 2.8 hours.... more
Intro to statistics
Suppose we want to estimate the average IQ score for the population of statistics students. What is the minimum number of statistics students that must be randomly selected for IQ tests if we want... more
probability in statistics
The number of hours an American adult sleeps each night follows a Normal distribution with an average of 6.9 hours per night with a standard deviation of 0.68 hours. If we randomly select one... more
Probability in statistics and standard deviation
The number of hours an American adult sleeps each night follows a Normal distribution with an average of 6.9 hours per night with a standard deviation of 0.68 hours. If we take a random sample of... more
Math Problem with Standard deviation and Expected Time
A survey was done on a group of people that asked the time, , it takes them to commute to work, rounded to the nearest 10 minutes. Use the probability distribution table below to answer Part 1-2.X... more
what is the z score?
the number of hits a particular website receives in a day is normally distributed with a mean of 6250 hits and a standard deviation of 480 hits. what is the Z score for a day in which the website... more
what is the likelihood a pack of gummy bears will contain between 37 and 45 candies?
the number of pieces in a pack of gummy bears is normally distributed with a mean of 35 and a standard deviation of 4. if a package is chosen at random what is the likelihood it will contain... more
what is katie's mark if she scored above the mean?
a teacher is analyzing the results for a test, the marks are normally distributed with a mean of 77.4 and a standard deviation of 4.2. determine katie's mark if she scores 2.5 standard deviations... more
What is the standard deviation of potential winnings in a casino session where a player makes 5957 bets on the number 17 for a total of 2,116,780$ and turned a net profit of $67,520?
I am trying to figure out what the standard deviation with regards to winnings in $$$ is, for the following Roulette session:The house edge in roulette is 5.26%, meaning we expect a player to lose... more
Probability & Distribution question
Thank you so much!! I really want to master this unit :(
Standard Deviation Probability
Approximately what percent of a standard normal distribution is found within each region? Hint: Drawing a graph may help.Note: Please enter your answers in percentages.a. Between the mean and one... more
What percent of scores would be above 592?
The national average for mathematics on a standardized test in 2011 was 502. Suppose that the distribution of scores was approximately bell shaped and that the standard deviation was approximately... more
percentage of population and probability of coin toss
hello there,I would to help me how to solve these two problems. 1- Assume the world human population heights follow a perfect normal distribution with standard deviation of 20 and mean of 150, what... more
A sample of n = 36 scores has a mean of M = 85 and a standard deviation of s = 24. What is the estimated standard error of the t-distribution of sample means (i.e., of the t-test for a single sample)? more
Mr. Johnson's class is normally distributed with a class average of 75% and a standard deviation of 6. What are the quartiles of Mr. Johnson's class?
Given the mean score on the test is 300 and the standard deviation is 30. What value on the test must a person score to be in the top 10%?
The scores are adjusted so that the mean score is about mu =75 and the standard deviation sigma =5. What percent of the scores fall between 65 and 75?
Farming Watermelon Statistics Question
What price do farmers get for their watermelon crops? In the third week of July, a random sample of 42 farming regions gave a sample mean of x = $6.88 per 100 pounds of watermelon. Assume that σ is... more
Mean and Percentage
5 million students appeared in an exam.The total marks of the exam were 9.0.Mean score of male candidates: 5.55/9.0Mean score of female candidates: 5.66/9.0How many students or what percentage of... more
Normal Distribution Question
Assume that x has a normal distribution with the specified mean and standard deviation. Find the indicated probability. (Round your answer to four decimal places.)μ = 4; σ = 2P(3 ≤ x ≤ 7)
Math Question on scores
The scores on a test are normally distributed with a mean of 150 and a standard deviation of 30. Find the score that is 1 and one half standard deviations above the mean.