10.1

1.

Consider the following hypothesis test. Ha: H, - H2 >0 The following results are for two independent samples taken from the two populations. Sample 1 Sample 2 n, = 40 n, = 50 X, = 25.4 X, = 22.8 0 = 5.5 0 , =6 (a) What is the value of the test statistic? (Round your answer to two decimal places.) (b) What is the p-value? (Round your answer to four decimal places.) (c) With a = 0.05, what is your hypothesis testing conclusion? O Do not reject Ho. There is insufficient evidence to conclude that #, - #2 > 0. O Do not Reject Ho. There is sufficient evidence to conclude that #, - #2 > 0. O Reject H . There is insufficient evidence to conclude that # , - (2 > 0. O Reject H . There is sufficient evidence to conclude that #, - (2 > 0.Consider the following data for two Independent random samples taken from two normal populations. (a) Compute the two sample means. Sample 1 Sample 2 (b) Compute the two sample standard deviations. (Round your answers to two decimal places.) Sample 1 Sample 2 (c) What is the point estimate of the difference between the two population means? (Use Sample 1 - Sample 2.) :l (d) What is the 90% condence interval estimate of the di'l'ferenoe between the two population means? (Use Sample 1 Sample 2. Round your answers to two decimal places.) :ltol:l ihe increasing annual cost (includng tuition, room, board, books, and fees) to attend college has been widely disoussed (limecom). The following landom samples show the annual cost ofattenolng private and public colleges. Data are in thousands of dollars. Private callegu Public Colleges 52.8 43.2 45.0 33.3 45.0 20.3 22.0 28.2 15.6 24.1 28.5 30.6 44.8 37.3 51.5 42.0 22.3 25.8 13.5 25.6 14.4 21.8 (a) Compute the sample mean {In thousnd dollars) and sample standard deviation (In thousand dollars) for pdvate colleges. (Rmnd the stardard deviation to two decimal places.) sample mean $ thousand sample standard deviation 5. thousand Compute the sample mean {in thousand dollars) and sample standard deviation (In thousand dollars) for public colleges. (Round the standard deviation to two decimal places.) sample mean 5 thousand sample standard deviation $ thousand (b) What Is the point estimate (In thousand dollats) of the difference between the two population means? (Use Private Public.) sEtmm Interpret this value In ten'ns of the annual post [in dollars) of attending private and public colleges. We estimate that the mean annual cost to attend pnvabe colleges Is $ :| more man the mean annual cost to attend public college (c) Develop a 95% condence Interval (in thousand dollars) of the difference between the mean annual cost of attending private and public colleges (Use Private Public. Round your answers to one decimal place.) 3; thousand in 5 :thousand College Grads High School Grads 501 503 442 492 534 517 580 478 650 526 479 425 554 410 486 485 566 499 528 390 588 562 524 535 497 464 592 469