Math 221 Study guides, Class notes & Summaries

From a random sample of 58 businesses, it is found that the mean time the owner spends on administrative issues each week is 21.69 with a population standard deviation of 3.23. What is the 95% confidence interval for the amount of time spent on administrative issues? A. (19.24, 24.14) B. (21.78, 22.60) C. (20.86, 22.52) D. (20.71, 22.67) C. (20.86, 22.52) If a confidence interval is given from 45.82 up to 55.90 and the mean is known to be 50.86, what is the margin of error? 2.52 5.0...

Statistics - ANSWER-The scientific discipline that provides methods to help us make sense of data Population - ANSWER-The entire collection of individuals or measurements about which information is desired Sample - ANSWER-A part of the population selected for study Descriptive Statistics - ANSWER-The branch of statistics that includes numerical, graphical, and tabular methods for organizing and summarizing data Inferential Statistics - ANSWER-The branch of statistics that includes me...

Question 1 0 / 2 pts (CO 1) A survey of 385 people who like wild sweaters found that 74% had a wild holiday sweater. What is the population and what is the sample? Population: people who like wild sweaters: Sample: the 385 people who had a wild holiday sweater Population: people who like sweaters; Sample: the 74% that had a wild holiday sweater Population: people who like wild sweaters; Sample: the 385 people who like wild sweaters Population: people who like wild sweaters; Sample: the ...

If A is an m × n matrix and if the equation Ax=b is inconsistent for some bb in Rm, then A cannot have a pivot position in every row.True If the equation Ax=b is inconsistent, then b is not in the set spanned by the columns of A.True If A is an m × n matrix whose columns do not span Rm, then the equation Ax=b is inconsistent for some b in Rm.True Any linear combination of vectors can always be written in the form Ax for a suitable matrix A and vector x.True The equation Ax=b is con...

Question 1 2 / 2 pts A student believes that there is a 90% probability of getting an A on the next test. This would be considered: Empirical probability Manufactured probability Subjective probability Classical probability Question 2 2 / 2 pts Given the following information, find the probability that a randomly selected student will be tall, but not

Question 1 2 / 2 pts (CO 4) Consider the following table: Age Group Frequency 18-29 983 30-39 784 40-49 686 50-59 632 60-69 541 70 and over 527 If you created the probability distribution for these data, what would be the probability of 30-39? 0.189 0.237 0.425 0.165 Question 2 2 / 2 pts (CO 4) Consider the following table of hours worked by part-time employees. These employees must work in 5 hour blocks. Weekly hours worked Probability 5 0.06 15 0.61 20 0.18 25 0.15 Fin...

Question 1 0 / 2 pts (CO 1) A survey of 385 people who like wild sweaters found that 74% had a wild holiday sweater. What is the population and what is the sample? Population: people who like wild sweaters: Sample: the 385 people who had a wild holiday sweater Population: people who like sweaters; Sample: the 74% that had a wild holiday sweater Population: people who like wild sweaters; Sample: the 385 people who like wild sweaters Population: people who like wild sweaters; Sample: the ...

The City of Rexburg reports that the nitrate concentration in the city's drinking water supply is between 1.59 and 2.52 ppm (parts per million,) and values outside of this range are unusual. We will assume μ−2σ=1.59 ppm and μ+2σ=2.52 ppm. It is reasonable to assume the measured nitrate concentration is normally distributed. Estimate the mean of the measured nitrate concentration in Rexburg's drinking water.(1.59+2.52)/2= 4.11/2= 2.055 Curvature Residual PlotIf the residual plot ...

MATH 221 Test 1 Questions And Answers With Complete Solution Statistics - CORRECT ANSWERS The scientific discipline that provides methods to help us make sense of data Population - CORRECT ANSWERS The entire collection of individuals or measurements about which information is desired Sample - CORRECT ANSWERS A part of the population selected for study Descriptive Statistics - CORRECT ANSWERS Th...

A random number generator is used to select a number from 1 to 100. What is the probability of selecting an even number? Correct Answer 0.50 What is the sample space of rolling two four-sided die? Correct Answer (1,2)(1,3)(1,4)(2,2)(2,3)(2,4)(3,4)(4,4) Consider the table below Response (number of cats owned); None One, Two, Three, Four or more Frequency; 659, 329, 52, 13, or 8 What is the probability that the next person asked has four or more cats? Correct Answer Less than 1% Consid...