Question

NOTE: The numerical values in this problem have been modified for testing purposes. Suppose composite scores on the ACT test for the high school graduating class in a certain year had mean 21 and standard deviation 5.2.In al, 1,799,243 students in this class took the test. Of these, 170,777 had scores higher than 28 and another 54,167 had scores exactly 28. ACT scores are always whole numbers. The exactly Normal N(21, 5.2) distribution can include any value, not just whole numbers. What is more, there is no area exactly above 28 under the smooth Normal curve. So ACT scores can be only approximately Normal. To illustrate this fact, find (a) the percent of ACT scores greater than 28 using the actual counts reported. (Enter your answer rounded to two decimal places.) percent: Enter numeric value (b) the percent of ACT scores greater than or equal to 28, using the actual counts reported. (Enter your answer rounded to two decimal places.) percent: (c) the percent of observations that are greater than 28 using the N(21, 5.2) distribution. (The percent greater than or equal to 28 is the same, because there is no area exactly over 28.) (Enter your answer rounded to two decimal places.) percent

Answer 1