Suppose a 95% confidence interval for the mean is (10, 12) when you know the value of the population standard deviation (sigma). If you HAD NOT known the value of sigma, would your confidence interval have been wider, narrower, or the same? wider the same narrower

Q: If n-25, -46, and s-5, construct a confidence interval at a 95% confidence level. Assume the data…

A: Givenn=25x=46s=5confidence level = 95%

Q: Which of the following is false about the margin of error of a confidence interval? O As confidence…

A: Which of the following is false about margin of error of confidence interval?

Q: You are conducting a quantitative research on the study habits and academic performance of the…

A: From the provided information, Standard deviation (σ) = 8 Confidence level = 95% Margin of error (E)…

Q: 1. A recent study of 25 motorists showed that they spent an average of P750 per week. The standard…

A: Note: since you have posted multiple independent questions in the same request we will solve the…

Q: Two random samples have sizes of 50 and 25. Which of the following is true for a 99% confidence…

A: Given that  Random sample sizes (n1) = 50  and (n2) = 25 Confidence level (C) = 99%    We know that…

Q: True or False: If the amount of gasoline purchased per car at a large service station has a…

A: It is given that the mean and standard deviation are 15 and 4, respectively.

Q: A researcher found that a cigarette smoker smokes on average 31 cigarettes a day. She feels that…

A: Computation of test statistic value: Sample size is smaller than 30 and the population standard…

Q: If a sample of 25 fish from my pond has mean weight 157 grams with a standard deviation of 8.3 grams…

A: Given: σ = 8.3 grams  n = 25

Q: Suppose you are testing the null hypothesis that a population mean is greater than or equal to 60,…

A: State the hypotheses. That is, the population mean equals 60. That is, the population mean is less…

Q: A sample of 47 Charleston County households have a mean income of $32,346 with a standard deviation…

A: The sample size is 47, sample mean is $32346, and sample standard deviation is $8571. The confidence…

Q: $alaries of 55 college graduates who have taken a statistics course have a mean of $43,797 and a…

A:

Q: Construct a​ 95% confidence interval about the mean age.

A: Given Data : Sample Size, n = 32 Sample Mean, x̄ = 37.3 sample…

Q: The General Social Survey asked: “How many e-mails do you send in a day?” The results of 928…

A: Given information Sample size n = 928 Mean x̅ = 10.4 Standard deviation s = 28.5 Since significance…

Q: 3 In a large city the distribution of incomes per family has a standard deviation of $5200. (i) For…

A: According to central limit theorem, if the population is normally distributed or sample size is at…

Q: A sociologist develops a test to measure attitudes towards public transportation, and 27 randomly…

A: Given information- Sample size (n) = 27 Mean x̅ = 73.8 Standard deviation (s) = 21.4 Significance…

Q: Suppose you calculate a 99% confidence interval to be: 13.05 to 20.75. Determine the margin of error

A: Given data: The given upper limit is b=20.75. The given lower limit is a=13.05.   The expression for…

Q: A random sample of 100 visitors to a popular theme park spent an average of $142 on the trip with a…

A: The confidence level is 0.98.

Q: The 2008 General Social Survey asked, “What do you think is the ideal number of children for a…

A: Given that,  n=678x¯=3.22s=1.99 The point estimate of the population mean is sample mean. That is,…

Q: using the confidence interval method, to test that population mean equals 14, a researcher obtains…

A: Solution: State the hypotheses. Null hypothesis: H0: µ=14. That is, the population mean is equal to…

Q: Suppose, according to a 1990 demographic report, the average U. S. household spends $90 per day.…

A:

Q: Find the 98% confidence interval for the difference between the means of the two populations

A: Given that sample size n = 18 Mean difference = 22.9 And SD sd = 2.2 The critical value of t at (n -…

Q: A random sample of 81 credit sales in a department store showed an average sale of $75.00. From past…

A: Solution: Let X be the amount of sale. From the given information, n=81, x-bar=$75 and σ=$27.

Q: For an SRS of 66 students, the average exam score was a 73. Assume you know the population standard…

A: Given,Standard deviation(σ)=10margin of error(E)=1.0α=1-0.99=0.01α2=0.005Z0.005=2.58     (from…

Q: Using a college cost estimator, the average of campus rental at Penn State is approximately $547 per…

A: Note: Hey, since there are multiple subparts are posted, we will answer first three subparts for…

Q: The number of television sets coming off a production line each day is known to have a standard…

A:

Q: The population standard deviation and sample standard deviation are of the same value if the…

A: The study is about the population standard deviation and sample standard deviation.

Q: A researcher is interested in the decrease in adolescent BMI after a new after school program is…

A:

Q: If the standard error of the mean is σx̅ = 3 and the sample size is n= 64,then the population…

A:

Q: How many commuters must be randomly selected to estimate the mean driving time of Chicago commuters…

A: Given Information: Confidence level = 90%  Error (e) = 4 minutes Standard Deviation (s) = 12 minutes…

Q: 7. If n=25 and the sample standard deviation is 15, construct a 95% confidence interval for the true…

A: We have given that, n = 25 , Standard deviation = 15, We need to construct the 95% confidence…

Q: A custodian wishes to compare two competing floor waxes to decide which one is best. He believes…

A:

Q: Find the length of a 99% confidence interval for the mean of the sample with a standard deviation of…

A: We have given that the 99% confidence interval for the mean of the sample with a standard deviation…

Q: Which of the following is false about the margin of error of a confidence interval? O As standard…

A: Given that, Which of the following is false about the margin of error of a confidence interval.

Q: In a random sample of 80 teenagers, the average number of texts handled in a day is 50. The 96%…

A: Given information: n = 80 μ=50 96% confidence interval for the mean number of texts handled by teens…

Q: If the standard error of the mean is σx̅ = 3 and the sample size is n = 64, then the population…

A:

Q: Suppose that you are preparing to construct a 98% confidence interval for the population mean.  You…

A: Given Data : Sample Size, n = 27 Sample Mean, x̄ = 29.5 standard deviation,…

Q: In this example, Ha is the mean value of the differences d for the population of all pairs of data,…

A: 6th  (X) 13 th (Y) D =X-Y (D-Dbar)^2 6 12 -6 1.96 10 13 -3 2.56 9 15 -6 1.96 5 10 -5 0.16…

Q: Suppose the variance of a sample is 7.3. Find the standard deviation. Round to two decimals.

A: Given : Variance , s2 = 7.3

Q: Five students took a self-confidence test. Their deviation scores were –4, +3, +1, –2, and +2.…

A: Given ,deviation scores were –4, +3, +1, –2, and +2

Q: Determine the margin of error for the confidence interval for the mean: 23 +1.7 The margin of error…

A: Confidence Interval is an inference process that is used to estimate the population parameter. The…

Q: According to Dietary Goals for the US (1977), high sodium intake may be related to ulcers, stomach…

A: We have given that, Mean(x̄) = 238, standard deviation (s) = 8.3, sample size (n) = 9 and confidence…

Q: If a sample of 4 fish from my pond has mean weight 157 grams with a standard deviation of 8.3 grams…

A: Given: n=4, x=157 and s=8.3   At 99% confidence level, the value of z is 2.576.

Q: A graduate student is performing a study on a new antidepressant. The drug is supposed to reduce…

A: The random variable score follows normal distribution. We have to test whether the average score for…

Q: You are told that a 95% confidence interval for the population mean is 17.3 to 24.5. If the…

A: we have to identify true or false.

Q: What is the smallest sample size required to provide a 95% confidence interval for a mean, if it…

A: We want to find the sample size  Given Margin of error=E=1 Standard deviation=σ=3 The critical value…

Q: Thirty randomly selected students took the calculus final. If the sample mean was 95 and the…

A: The summary of statistics is, The degree of freedom is, Critical value: By using the t-tables, the…

Q: True or False? If a 90% confidence interval for the mean is (75.3 to 80.9), we would reject H0=70 in…

A: It is an important part of statistics. It is widely used.

Q: A student was asked to find a 95% confidence interval for the proportion of students who take notes…

A: It is given that a student was asked to find a 95% confidence interval for the proportion of…

Q: Bob makes a 95% confidence interval with a random sample of 100 and his margin of error is plus or…

A: Here we need to choose from the correct option.

Percentage

A percentage is a number indicated as a fraction of 100. It is a dimensionless number often expressed using the symbol %.

Algebraic Expressions

In mathematics, an algebraic expression consists of constant(s), variable(s), and mathematical operators. It is made up of terms.

Numbers

Numbers are some measures used for counting. They can be compared one with another to know its position in the number line and determine which one is greater or lesser than the other.

Subtraction

Before we begin to understand the subtraction of algebraic expressions, we need to list out a few things that form the basis of algebra.

Addition

Before we begin to understand the addition of algebraic expressions, we need to list out a few things that form the basis of algebra.