Suppose that we draw a sample of size 49 from a population which has an incomplete gamma distribution having a mean value of 40 and a variance of 7. What will be the distribution of the sample mean (with its parameters)?

The data from an independent-measures research study produce a sample mean difference of 4 points, and each sample has a variance of 10. If there are n = 20 scores in each sample, then what is the estimated standard error of the difference between means?

suppose that we have disjoint normal populations A and B and we want to find the standard error estimate for estimating the difference in their means. We have an IRS from A of size 8 with variance 25 and an IRS from B of size 9 with variance 16.  What is the resulting standard error estimate if we assume both populations have the same population variance?

Records from previous years for a casualty insurance company show that its clients average a combined total of 1.9 auto accidents per day, with a variance of 0.31. The actuaries of the company claim that the current variance, oʻ, of the number of accidents per day is not equal to 0.31. A random sample of 17 recent days had a mean of 2 accidents per day with a variance of 0.62. If we assume that the number of accidents per day is approximately normally distributed, is there sufficient evidence to conclude, at the 0.05 level of significance, that the actuaries are correct? Perform a two-tailed test. Then complete the parts below. Carry your intermediate computations to three or more decimal places and round your answers as specified below. (If necessary, consult a list of formulas.) (a) State the null hypothesis H, and the alternative hypothesis H,. p H, :0 H, :0 (b) Determine the type of test statistic to use. (Choose one) ▼ D=0 OSO O20 (c) Find the value of the test statistic. (Round…

Suppose that the blood pressure for a randomly selected patient has an average of 22 and variance of 441. If a sample of 220 patients is selected, then what is P(-1.2 < X< 1.4) ?

Give a 99.8% confidence interval, for μ₁ −μ₂ given the following information. n₁ = 35, x₁ = 1 2.41, s₁ = 0.39 81 n₂ = 20, x₂ = 2.62, s₂ = 0.83 2 -0.21 ✓0.69 X Use Technology Rounded to 2 decimal places.

You are testing the claim that having lights on at night increases weight gain (abstract). A sample of 10 mice lived in an environment with bright light on all of the time and 8 mice who lived in an environment with a normal light/dark cycle is given below. Test the claim using a 2% level of significance. Assume the population variances are unequal and that the weight changes are normally distributed. Give answers to 3 decimal places. Data available at StatKey, choose Mice Wgt Gain-2e data set Light (1) 1.71 4.67 4.99 5.33 5.43 6.94 7.15 9.17 10.26 11.67 What are the correct hypotheses? Note this may view better in full screen mode. Select the correct symbols in the order they appear in the problem. Ho: ₁ Test Statistic = Dark (₂) 2.27 2.53 2.83 4 4.21 4.6 5.95 6.52 Ha: ₁ Based on the hypotheses, find the following: p-value = = V Select an answer ✓ Select an answer (Hint: difference in means from H₂) The correct decision is to fail to reject the null hypothesis The correct summary…