The average monthly gas bill of a random sample of 43 residents of a city is $185 with a standard deviation of $32. Assume the gas bills are normally distributed. Construct a 99% confidence interval for the population mean monthly gas bills of all residents.

Q: The GPA of accounting students in a university is known to be normally distributed. A random sample…

A: A random sample of 26 accounting students has a mean of 2.61 and a standard deviation of 0.13.

Q: A researcher collected sample data for 11 women ages 18 to 24. The sample had a mean serum…

A:

Q: Researchers found that in certain counties in the country, females spend an average of 65 days in…

A: standard deviationσ=4n=36x¯=65

Q: A random sample of 40 students taken from a university showed that their mean GPA is 2.94 and the…

A: Obtain the 99% confidence interval for the population mean GPA of students: Denote the population…

Q: How large a sample should be selected to provide a 90% confidence interval with a margin of error of…

A:

Q: A random sample of 21 Camden County College students had a mean age of 24 years, with a standard…

A:

Q: The number of cars sold annually by used car salespeople is normally distributed with a standard…

A: Given, Standard Deviation =σ=4.7Sample size =n = 47Mean = x=28

Q: The lengths of pregnancies in a small rural village are Normally distributed with a mean of 270 days…

A:

Q: A sample of 60 people who were chosen for a sample had an average IQ score of 105. If the population…

A: From the given, x¯ (mean IQ score from sample)=105n (sample size)=60σ (population SD of IQ…

Q: Find a 90% confidence interval for the population standard deviation if you are given a sample of 10…

A: Given data : sample size,n = 10 df=n-1= 9 sample standard deviation,s= 3.0…

Q: The average income among a sample of 75 students studying at University of Chichester is found to be…

A: sample size(n)=75Mean()=50standard deviation(s)=13confidence interval=95%

Q: A certain counselor wants to compare mean IQ scores for two different social groups. A random sample…

A: Given that    Sample sizes n1=13    , n2=11      Sample means X̄1=103      , X̄2=116      s1 =15…

Q: were found to have an average weight of 9.7 ounces with a sample standard deviation is 0.20. Find…

A: As the population standard deviation is not known, we will use t distribution. Degrees of freedom…

Q: A sample of only 8 adult rhinos had an average weight of 2,500 pounds. The standard deviation for…

A:

Q: A researcher collected sample data for 17 women ages 18 standard deviation of 9.3. Assuming that…

A:

Q: A survey of 38 men found that the standard deviation is 3.3 and the average number of units for…

A: The sample size for men is 38, standard deviation is 3.3, and mean is 12.8. The sample size for…

Q: The lengths of human pregnancies are normally distributed with a mean of 268 days, and a standard…

A: Given that, X~N(268,152) n=10

Q: use this to find a 95% confidence interval for the mean height of all red maple trees

A: The sample size is n = 146 Sample mean = 59 And sample SD = 12 Since the sample size is large then…

Q: A random sample of 40 Americans yielded a sample mean of 67 gallons of carbonated beverages per…

A: We have given that,  Sample mean (x̄) = 67, Population standard deviation (σ) = 22 and sample size…

Q: Find a 90% confidence interval for the mean of a normal distribution if population variance is 4 and…

A: Given CL = 0.90 Population variance, σ2=4 Sample size, n=8 9,14,10,12,7,13,11,12

Q: x¯ = Margin of error at 90% confidence level = 90% confidence interval =

A: Given: n=8 Confidence level=90% Height, X 67 66 64 75 63 67 72 71

Q: A researcher has collected the blood samples of 29 individuals and found that the mean hemoglobin…

A: Given information :  A researcher has collected the blood samples of 29 individuals and found that…

Q: Suppose we are contracted by the Justice Department to study the extent of juvenile delinquency.  We…

A:

Q: The distribution of study times for first-year students follows a normal distribution with a…

A:

Q: If the mean and standard deviation of a sample of size 45 is 1050 and 52 respectively, construct a…

A: It is given that Sample mean = 1050Sample standard deviation = 52Sample size = 45Confidence level =…

Q: random sample of 15 students was selected from a population size of 100 (normal) in a certain…

A:

Q: A researcher makes a research about the life time of batteries which have a normal distribution. In…

A: From the given information, Sample size n =49 Sample mean, x̅=48 hours Sample standard deviation,…

Q: researcher collected sample data for 16 women ages 18 to 24 . The sample had a mean serum…

A:

Q: find the 99% confidence interval of the mean number of miles driven per day by all truckers

A: It is given that  Average = 540 Population standard deviation = 40 Sample size = 90

Q: A researcher collected sample data for 20 women ages 18 to 24. The sample had a mean serum…

A:

Q: In a random sample of six mobile​ devices, the mean repair cost was ​$65.00 and the standard…

A:

Q: A random sample of 5 months in an urban area showed an average of 28 mail carriers were bitten by…

A: Here we need to construct a 95% confidence interval for the mean number of mail carriers who were…

Q: How large a sample should be selected to provide a 99% confidence interval with a margin of error of…

A:

Q: An agriculture researcher plants twenty five plots with a new variety of corn. The average yielded…

A: Given that,   Critical value: By using the z-tables, the critical value at 10% level of…

Estimation

A new framework of data analysis where the new statistical methods are used for interpreting the results and analyzing the data is known as estimation in statistics.