The formula for estimating the number of people, nn, that need to be surveyed in order to have a specified margin of error with a specified level of confidence for the average age of first kiss is given by n=z^2*stdDev^2/E^2 where z=2.266 depends on the level of confidence, stdDev is the standard deviation and E is the margin of error. How many people need to be surveyed if the standard deviation is 1.939 years and the margin of error is 0.122 years. n = (Please always round your answer up to the smallest whole number that is greater than or equal to your answer.)

The mean life span of an African savanna elephant in the wild used to be 60 years. A recent sample of 15 deceased elephants in the wild yielded a mean life span of 62 years. Assume a normally distributed population with = 6 years. Test if the population mean life span of African savanna elephants has increased, using a = 0.05. Select one: O a. p-value = 0.0984, do not reject Ho. O b. p-value = 0.0984, reject Ho. c. p-value = 0.1968, do not reject Ho. d. p-value = 0.4522, do not Reject Ho.

High density lipoprotein (HDL) in healthy males follows a normal distribution with a mean of 50 and a standard deviation of 8. What proportion of healthy males has HDL exceeding 60?

A manufacturer knows that their items have a normally distributed lifespan, with a mean of 7.1 years, and standard deviation of 2.2 years. The 8% of items with the shortest lifespan will last less than how many years? Please show your answer to one decimal place. # of years =

The length of human pregnancies from conception to birth is known to be normally distributed with a mean of 266 days and standard deviation of 16 days. A pregnancy longer than "nine months" might be considered as 274 days or longer (four months have 30 days, and February has 28 in most years). What proportion of pregnancies last more than "9 months?" First, find the z-score for 274: (274 -266)/16 0.5. Then, find the area to the of 0.5, using the table. Your answer Need help on this question? Read the ebook page on this topic (1no penaltyi Geta hint (fewer pelnte Show answer (nopoint

An old medical textbook states that the mean sodium level for healthy adults is 140 mEq per liter of blood. A medical researcher believes that, because of modern dietary habits, the mean sodium level for healthy adults, u, now differs from that given in the textbook. A random sample of 23 healthy adults is evaluated. The mean sodium level for the sample is 147 mEq per liter of blood. It is known that the population standard deviation of adult sodium levels is 14 mEq. Assume that the population is normally distributed. Can we conclude, at the 0.10 level of significance, that the population mean adult sodium level differs from that given in the textbook? Perform a two-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places, and round your responses as specified below. (If necessary, consult a list of formulas.) (a) State the null hypothesis H and the alternative hypothesis H₁. H₂:0 H₁ :0 (b) Determine the type of test statistic to…

Among 157 Cuban American men ,the mean systolic blood pressure was 146 mm Hg with a standard deviation of 27. We wish to know if based on these data, we may conclude that the mean systolic blood pressure for a population of Cuban American is greater than 140. Use α=0.01 (solve without excel) , show work

A random sample of 51 adult coyotes in a region of northern Minnesota showed the average age to be x = 2.01 years, with sample standard deviation s = 0.76 years. However, it is thought that the overall population mean age of coyotes is u = 1.75. Do the sample data indicate that coyotes in this region of northern Minnesota tend to live longer than the average of 1.75 years? Use a = 0.01. (a) What is the level of significance? State the null and alternate hypotheses. O Ho: H 1.75 yr; Hi: и 1.75 yr; Hi: и %3D 1.75 yr II Но: и 3 1.75 уr; Hi: и > 1.75 yr Ho: H = 1.75 yr; H1: µ # 1.75 yr (b) What sampling distribution will you use? Explain the rationale for your choice of sampling distribution. O The standard normal, since the sample size is large and o is known. The Student's t, since the sample size is large and o is known. The standard normal, since the sample size is large and o is unknown. O The Student's t, since the sample size is large and o is unknown. What is the value of the…

Adult men have heights with a mean of 69.0 inches and a standard deviation of 2.8 inches. Find the height of a man with a z-score of -1.3 (to 2 decimal places)

An old medical textbook states that the mean sodium level for healthy adults is 138mEq per liter of blood. A medical researcher believes that, because of modern dietary habits, the mean sodium level for healthy adults, μ, now differs from that given in the textbook. A random sample of 60 healthy adults is evaluated. The mean sodium level for the sample is 142mEqper liter of blood. It is known that the population standard deviation of adult sodium levels is13 mEq. Can we conclude, at the 0.05 level of significance, that the population mean adult sodium level differs from that given in the textbook? Perform a two-tailed test. Then complete the parts below.Carry your intermediate computations to three or more decimal places, and round your responses as specified below. (If necessary, consult a list of formulas.) (For z test statistics) every expert has gotten the z test statistic wrong thus far. I have included pictures of a sample problem and formula. A. State the null hypothesis H0 and…