A sample of 20 heads of lettuce was selected. Assume that the population distribution of head weight is normal. The weight of each head of lettuce was then recorded. The mean weight was 2.2 pounds with a standard deviation of 0.1 pounds. The population standard deviation is known to be 0.2 pounds. a. Find the z-scores that corresponds to a 90% confidence interval from the normal table. b. Find the error bound (margin of error) for a 90% confidence interval for the population mean weight of the heads of lettuce. Round to three decimal places.

Q: The prices of used books at a large college bookstore are normally distributed. If a sample of 23…

A: From the provided information, Sample size (n) = 23 Sample mean (x̅) = $27.50 Sample standard…

Q: Find the 2-score for a raw score of 27 with a mean of 20 and a standard deviation of 5. O-06 O 14 O…

A:

Q: sample of seven containers of fuel have a mean content of 10.0 liters with standard deviation of…

A:

Q: use the given information to find the minimum sample size required to estimate an unknown population…

A: Standard Deviation = σ = 89 Margin of Error = E = 5 Confidence Level = 95 Significance Level =…

Q: The American Veterinary Association claims that the annual cost of medical care for dogs averages…

A: Given  The annual cost for medical care  for dogs average    =  $100 SD             = $30 for cats…

Q: Use the given data to find the 95% confidence interval estimate of the population mean µ. Assume…

A: Given that  n = 25 mean = 104 s = 15

Q: In a large population of college-educated adults, the mean IQ is 112 with standard deviation 50.62.…

A: We have given that Mean(µ) = 112Standard deviations (σ) = 50.62n = 30

Q: Given that the population standard deviation is σ = 1, determine the minimum sample size needed in…

A: Solution Refer Standard normal table/Z-table OR use excel function…

Q: W 4. A cell phone company claims that the average time a person spends on their phone is 12.8 hours…

A: Let μ denote the population mean and x⎯⎯ denotes the sample mean. Then, μ=12.8 and x⎯⎯=12.2 Let n be…

Q: find the t/α2 value for an 85% confidence interval for the mean when the sample size is 12

A: We have to find correct answer..

Q: In the course of designing theater seats, the sitting heights (in mm) of a simple random sample of…

A: Given information: Total number of adult women(n) is 12. Meanx¯ of height of 12 women is 834 mm.…

Q: A statistics practitioner took a random sample of 50 observations from a population whose standard…

A: It is given that sample mean is 100 and the standard deviation is 25.

Q: he population standard deviation is σ=2σ=2, determine the minimum sample size needed in order to…

A: The sample size can be calculated as: n=z×σE2 Here, z = desired confidence level E = The allowable…

Q: Use the given data to find the 95% confidence interval estimate of the population mean u. Assume…

A: Given data: sample size = 25 Standard deviation = 13 Sample mean = 106 Confidence level = 95%

Q: A preliminary sample of holiday shoppers revealed that the standard deviation of the amount of money…

A: Given data,σ=82E=7z-value at 95% confidence is Zc=1.96n=?

Q: Find the critical value, for a 90% confidence when the sample size is 22.

A:

Q: For a normally distributed population with a mean of 35 and a standard deviation of 7.5 find P(X <…

A:

Q: A certain machine makes electrical resistors having a mean resistance of 50 ohms and a standard…

A: As per our guidelines we are suppose to answer only one question.

Q: find the t/α2 value for a 98% confidence interval for the mean when the sample size is 39.  t/α2=

A: The objective is to find the critical value for 98% confidence interval for the mean.

Q: In a reaction between an aqueous solution of AgNO3 + NaCl, the following percentages of chloride…

A: Given information- We have given the percentages of chloride found in aqueous solution. 32.52%,…

Q: For a group of 15 men subjected to a stressful situation, the mean number of heartbeats per minute…

A: Sample size (n) = 15Sample mean (x̅) = 126Standard deviations (s) = 4 Significance level (α) = 1-…

Q: Given that the population standard deviation is o = 1, determine the minimum sample size needed in…

A:

Q: Robrigado noted that the mean scores of a random sample of 15 Grade 8 students who had taken a…

A: A point estimate is defined as the single value, which is calculated from the sample data, to serve…

Q: Use the given information to find the minimum sample size required to estimate an unknown population…

A: Margin of error, M.E = $500 Confidence level (α) = 95% σ =$1500

Q: opulation with a standard deviation of  20, find the z-score for each of the following locations in…

A: The z score can be calculated as: z=x-μσ (a) The z score for Above the mean by 5 points is,…

Q: In a factory producing glasses, the weights of glasses are known to have a mean of 160 grams. It is…

A: By looking at a Z table we can conclude that Q1 and Q3 are each .6745 standard deviations from the…

Q: Use The t Distribution Table to find the t/α2 value for a 98% confidence interval for the mean when…

A: Given that n = 17 Degrees of freedom = df = n - 1 = 17 - 1 = 16 t/α2 value for a 98% confidence…

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: Find the critical value, t c,  used for a 90% confidence interval for the mean with a sample size of…

A: The confidence level is, 100 (1 – α) % = 90%. Hence, (1 – α) = 0.90, and the significance level is,…

Q: for a sample of 150 that has a mean of 6540 and a standard deviation of .89, calculate the 95%…

A: It is given that mean and standard deviation are 6,540 and 0.89, respectively.

Q: For a normally distributed population with a mean of 35 and a standard deviation of 7.5 find P(X <…

A:

Q: D. The temperature readings for 20 days in Sydney are normally distributed with a mean of 5.5°C and…

A:

Q: A sample of 150 brand A light bulbs showed a mean lifetime of 1392 hours and a standard deviation of…

A: Option C is correct

Q: For a population with a mean of μ = 100 and a standard deviation of σ = 20, Find the score (X…

A:

Q: Ten years after graduation, the salaries of Heriot-Watt University graduates are Normally…

A: Let X ~ Normal( 55000, 11000)

Q: Given a normally distributed set of scores with mean = 86.5 and standard deviation a = 11.4,…

A: Z-scores provides the information about the location of the scores in terms of standard deviation.…

Q: Given that X is normally distributed with a mean of 50 and a standard deviation of 4, determine P(45…

A:

Q: for a sample of 57 that has a mean of 6200 and a standard deviation of 254, calculate the 95%…

A:

Q: Suppose that the waiting times for patients at a local hospital are normally distributed with a…

A: Given,Standard deviation σ = 30Sample size n = 75Sample mean x¯ = 90

Q: Use The t Distribution Table to find the t2 value for a 98% confidence interval for the mean when…

A: Obtain the degrees of freedom.   The degrees of freedom is obtained below as follows:   From the…

Q: Use the given data to find the 95% confidence interval estimate of the population mean µ. Assume…

A: (1-α)% CI for μ is X-tα/2S/n≤μ≤X+tα/2S/n

Q: Find the critical value, for a 90% confidence when the sample size is 22

A:

Q: For a population with a mean of μ= 40 and a standard deviation of σ= 6, find the z-score…

A: From the provided information, Population mean (µ) = 40 Standard deviation (σ) = 6 a) Sample size…

Q: The cell phone conversations of a random sample of 50 students has a standard deviation of 9.7…

A: Given: n=50σ=9.7CI=90%=0.90

Q: Miss Robrigado noted that the mean scores of a random sample of 15 Grade 8 students who had taken a…

A: Given data,n=15x=80.5s=3.1α=0.05

Q: Use the given information to find the minimum sample size required to estimate an unknown population…

A: Determine the sample size n needed. Obtain the critical value of z at the 95% confidence level.…

Q: Use the given information to find the minimum sample size required to estimate an unknown population…

A:

Q: An engineer is taking density readings along a recently constructed earthen dam. If the sample…

A:

Q: se the given degree of confidence and sample data to construct a confidence interval for the…

A: We have given that  Sample size n= 30 Sample mean = 90 Standard deviation = 6.7 99% confidence…

Q: For a normal distribution with a variance σ^2, how large a sample would we need to ensure that the…

A: The (1-α) confidence interval for μ is, CI=x¯±zσnHere,L=x¯-zσnU=x¯+zσn