# Statistics

All new and solved questions in Statistics category

##### Based on data collected by the National Center for Health Statistics and made available to the public in the Sample Adult database, an estimate of the percentage of adults who have at some point in their life been told they have hypertension is 23.53 perc
Based on data collected by the National Center for Health Statistics and made available to the public in the Sample Adult database, an estimate of the percentage of adults who have at some point in their life been told they have hypertension is 23.53 percent. If we select a simple random sample of 2...
##### In an effort to increase production of an automobile part, the factory manager decides to play music in the manufacturing area
in an effort to increase production of an automobile part, the factory manager decides to play music in the manufacturing area. Eight workers are selected, and the number if items each produced for a specfic day is recored. After one week of music, the same workers are monitored again. The data are ...
##### 47 65 42 47 16 36 54 17 21 58 16 31 32 13 22 The following list contains P/E ratios (price of stock divided by projected earnings per share) for health care companies
47 65 42 47 16 36 54 17 21 58 16 31 32 13 22The following list contains P/E ratios (price of stock divided by projected earnings per share) for health care companies. Find th and th percentiles for these ratios....
##### He owners of a two-person business make their decisions independently of each other and then compare their decisions
he owners of a two-person business make their decisions independently of each other and then compare their decisions. If they agree, the decision is made; if they do not agree, then further consideration is necessary before a decision is reached. Each has a history of making the right decision 55% o...
##### Bob received a z score of 0.9 on a college entrance exam
bob received a z score of 0.9 on a college entrance exam. If the raw scores have a mean of 540 and a standard deviation of 80 points,what is his raw score?...
##### Total plasma volume is important in determining the required plasma component in blood replacement theory for a person undergoing surgery
Total plasma volume is important in determining the required plasma component in blood replacement theory for a person undergoing surgery. Plasma volume is influenced by the overall health and physical activity of an individual. Suppose that sample of 50 male firefighters are tested and that they ha...
##### A researcher interested in relationships developed a questionnaire that measures the degree of affection adult men feel for their fathers
A researcher interested in relationships developed a questionnaire that measures the degree of affection adult men feel for their fathers. She has found that for the general population the distribution is skewed to the right, the mean degree of affection is 60, and the standard deviation is 16. The ...
##### In a group of 100 students, 60 are taking math and 12 are taking English, but no one is taking both
In a group of 100 students, 60 are taking math and 12 are taking English, but no one is taking both. What is the probability that a randomly selected student from this group is taking either math or English?...
##### I'm stumped on this question
I'm stumped on this question. A teacher informs her history class that a test is very difficult, but the grades would be curved. Scores for the test are normally distributed with a mean of 25 and a standard deviation of 5. If the grades are curved according to the following scheme, find the nume...
##### In a certain microwave oven on the high power setting, the time it takes a randomly chosen kernel of popcorn to pop is normally distributed with a mean of 140 seconds and a standard deviation of 25 seconds
In a certain microwave oven on the high power setting, the time it takes a randomly chosen kernel of popcorn to pop is normally distributed with a mean of 140 seconds and a standard deviation of 25 seconds. What percentage of the kernels will fail to pop if the popcorn is cooked for (a) 2 minutes? (...
##### 12) The regression equation Credits = 15.4 -
12) The regression equation Credits = 15.4 - .07 Work was fitted from a sample of 21 statistics students. Credits is the number of college credits taken and Work is the number of hours worked per week at an outside job. A) Interpret the slope. B) Is the intercept meaningful? Explain. C) Make a predi...
##### Instructions for Data Sets: Choose one of the data sets A − J below or as assigned by your instructor
Instructions for Data Sets: Choose one of the data sets A − J below or as assigned by your instructor. Only the first 10 observations are shown for each data set (files are on the CD). In each data set, the dependent variable (response) is the first variable. Choose the independent variables (...
##### Assuming that the heights of college women are normally distributed with mean 62 inches and standard deviation 3.5 inches, what percentage of women are between 58.5 inches and 72.5 inches
Assuming that the heights of college women are normally distributed with mean 62 inches and standard deviation 3.5 inches, what percentage of women are between 58.5 inches and 72.5 inches? (Points: 5) 34.1% 84.0% 15.7% 13.6% 97.6%...
##### The Computer Anxiety Rating Scale (CARS) measures an individual's level of computer anxiety, on a scale from 20 ( no anxiety) to 100 (highest level of anxiety)
The Computer Anxiety Rating Scale (CARS) measures an individual's level of computer anxiety, on a scale from 20 ( no anxiety) to 100 (highest level of anxiety). Researchers at Miami University administered CARS to 172 business students. One of the objectives of the study was to determine whether...
##### A person's level of blood glucose and diabetes are closely related
A person's level of blood glucose and diabetes are closely related. Let x be a random variable measured in milligrams of glucose per deciliter (1/10 of a liter) of blood. Suppose that after a 12-hour fast, the random variable x will have a distribution that is approximately normal with mean of 7...
##### An admissions director wants to estimate the mean age of all students enrolled at a college
An admissions director wants to estimate the mean age of all students enrolled at a college. The estimate must be within one year of the population mean. Assume the population of ages is normally distributed. Determine the minimum required sample size to construct a 80% confidence interval for the p...