Vocab
Formulas
Variables
Confidence Intervals
Z-scores
100
Rolling a die is an example of a ______ random variable.
discrete
100
What is the formula for a standard z-score?
100
What is the symbol and name used to identify a population mean?
μ
100
What is the z* used in constructing a 95% 𝑧-confidence interval?
1.96
100
The weights of deer are normally distributed with a mean of 100 lb and a standard deviation of 25 lb. What is the maximum weight a deer can be if it is in the lower 23% of the weight of all deer?
81.5
200
Statistic is to Sample as _______ is to Population.
Parameter
200
What is the formula for a standard (population) Margin of Error?
200
What is the value that describes the value n?
sample size
200
We know that a 92% confidence interval for a mean is (0.258, 0.674). What is the mean for this confidence interval?
0.466
200
The exam scores for an introductory statistics class are normally distributed with a mean of 75 points and a standard deviation of 10 points. What score would a student need to earn to be in the top 10% of all students taking the exam?
87.8
300
What is the most basic and reliable form of sampling and the most common we see in this class?
Simple Random Sampling
300
What is the formula for solving for confidence intervals?
x̄ ± z*(σ/√n)
300
What is the value that describes the variable σ?
standard deviation
300
We know that a 92% confidence interval for a mean is (0.258, 0.674). What is the margin of error for this confidence interval?
0.208
300
The average amount of money college students spend on groceries each month is normally distributed with a population mean of $300 and a population standard deviation of $80. A researcher takes a random sample of 64 college students. What is the minimum sample average grocery expense needed for the sample to fall in the top 5% of all possible samples of 64 students?
316.45
400
In Probability, the list of all possible outcomes from an event is called what?
sample space
400
What is the formula to solve for the sample size needed for a given Margin of Error?
400
What is the symbol that correlates with the confidence level?
z*
400
A company want to estimate the mean number of hours employees work remotely each week. The sample mean is 18.4 hours, with a population standard deviation of 4.2, and n = 49. Construct a 95% confidence interval for the population mean.
(17.22, 19.58)
400
The number of hours students spend studying per week is normally distributed with a population mean of 15 hours and a population standard deviation of 6 hours. A researcher takes a random sample of 36 students. What is the maximum sample average study time for the sample to fall within the lowest 2.5% of all possible samples of 36 students?
13.04