Question

2. It has been reported that the average credit card debt for college series is $ 3260. The student serate at a large university feels that their, their seniors have a debt. much less than this : So it conducts a study of 47 randomly selected seniors and finds that therardoint sample has an average debt of $ 2995, with a headpoby deviation of $1100. Is the student Schinto correct Use a 001 (Murst State Ho, Ho, the Rejection Region, Test Statistic calénlátion, and conclusion .

Answer 1

From the given information, n = 47.5 = 2995.0 =1100, u = 3260 and a = 0.01 The critical value of the test at a =0.01 using normal tables is 2.33. Decision rule: The null hypothesis is rejected if the test statistic is less than the left critical value or greater than the right critical value. The null and alternative hypothesis of the test is, Null hypothesis H:u=3260 Alterative hypothesis H:\<3260 The test statistic is, z=1-4 V12 2995-3260 1100 V47 -265 160.4515 -1.65 Z Here the test statistic -1.65 is greater than the left critical value -2.33, so the null hypothesis is not rejected. Therefore, there is no enough evidence to conclude that the seniors in the college have an average credit card debt less than $3260.