Income 47.8 47.2 55.5 41.2 21.3 42.4 51.9 32.8 30.2 38.5 41.7 42.6 127.8 45.7 42.4 25.0 25.3 24.4 60.6 31.1 31.4 105.3 73.7 37.7 61.2 43.2 39.3 69.0 43.4 91.0 56.9 38.8 25.2 30.4 23.8 36.2 65.0 25.1 34.9 23.6 55.2 30.0 68.4 91.1 34.1 76.7 38.0 48.7 37.7 56.1 Check whether the median annual income for college graduate is $37,700 (37.7 thousand dollars). The hypotheses are H 0 : 37.7 against H1 : 37.7 The level of significance, Find the difference between sample values and 37.7. There are 17 observations below 37.7 (negative signs), 2 observations equal to 37.7 (zeroes) and 31 observations above 37.7 (positive signs). The test statistic, u min ve signs, ve signs min 17,31 17 Since the total number of valid observations are 48 (more than 30), use Z-test statistic to test the above hypothesis. Then, the Z-statistic, Z u 0.5 n 2 17.5 24 1.8764 n 12 2 The P-value = P Z 1.8764 1 P Z 1.8764 1 0.0303 0.9697 Since the P- value is more than the significance level (0.05), reject the null hypothesis. Hence, conclude that the median annual income for college graduates with a bachelor's degree is more than $37,700