Young's modulus is a quantitative measure of stiffness of an elastic material. Suppose that for metal sheets of a particular type, its mean value and standard deviation are 75 GPa and 2.1 GPa, respectively. Suppose the distribution is normal. (Round your answers to four decimal places.) n USE SALT (a) Calculate P(74 sXS 76) when n = 25. (b) How likely is it that the sample mean diameter exceeds 76 when n = 49? You may need to use the appropriate table in the Appendix of Tables to answer this question.

nutritionist claims that the mean tuna consumption by a person is 3.4 pounds per year. A sample of 90 people shows that the mean tuna consumption by a person is 3.3 pounds per year. Assume the population standard deviation is 1.02 pounds. At α=0.03​, can you reject the​ claim?       ​(a) Identify the null hypothesis and alternative hypothesis.     A. H0​: μ=3.4 Ha​: μ≠3.4 Your answer is correct.   B. H0​: μ>3.4 Ha​: μ≤3.4   C. H0​: μ≤3.3 Ha​: μ>3.3   D. H0​: μ≤3.4 Ha​: μ>3.4   E. H0​: μ>3.3 Ha​: μ≤3.3   F. H0​: μ≠3.3 Ha​: μ=3.3 ​(b) Identify the standardized test statistic.   z=negative 0.93−0.93 ​(Round to two decimal places as​ needed.) ​(c) Find the​ P-value.   0.3520.352 ​(Round to three decimal places as​ needed.) ​(d) Decide whether to reject or fail to reject the null hypothesis.

You want to obtain a sample to estimate a population mean. Based on previous evidence, you believe the population standard deviation is approximately σ=68.1σ=68.1. You would like to be 90% confident that your estimate is within 1 of the true population mean. How large of a sample size is required? Do not round mid-calculation.n =

Young's modulus is a quantitative measure of stiffness of an elastic material. Suppose that for metal sheets of a particular type, its mean value and standard deviation are 75 GPa and 2.5 GPa, respectively. Suppose the distribution is normal. (Round your answers to four decimal places.) n USE SALT (a) Calculate P(74 < X < 76) when n = 16. (b) How likely is it that the sample mean diameter exceeds 76 when n = 25?

Young's modulus is a quantitative measure of stiffness of an elastic material. Suppose that for metal sheets of a particular type, its mean value and standard deviation are 70 GPa and 2.4 GPa, respectively. Suppose the distribution is normal. (Round your answers to four decimal places.) n USE SALT (a) Calculate P(69 < XS 71) when n = 25. (b) How likely is it that the sample mean diameter exceeds 71 when n = 49?

A population of values has a normal distribution with μ=79.3 and σ=48.9. You intend to draw a random sample of size n=214.What is the mean of the distribution of sample means?μ¯x=What is the standard deviation of the distribution of sample means?(Report answer accurate to 2 decimal places.)σ¯x=

You want to obtain a sample to estimate a population mean. Based on previous evidence, you believe the population standard deviation is approximately σ=46.9σ=46.9. You would like to be 95% confident that your estimate is within 2 of the true population mean. How large of a sample size is required?n =

Assume that the body mass index (BMI) of all American young women follows a Normal distribution with standard deviation σ = 7.5. How large a sample would be needed to estimate the mean BMI μ in this population to within ±1 with 95% confidence? (Enter your answer as a whole number.)

Assume that the helium porosity (in percentage) of coal samples taken from any particular seam is normally distributed with true standard deviation 0.78. (c) How large a sample size is necessary if the width of the 95% interval is to be 0.31? (Round your answer up to the nearest whole number.) ? specimens (I have answers for a, b, and d I just need help with c, the answer is not 24.32)