The College Board National Office recently reported that in 2011-2012, the547,038 high school juniors who took the ACT achieved a mean score of 530 with a standard deviation of 123 on the mathematics portion of the test. Assume these test scores are normally distributed. d. How high does a student have to score to be in the top 10% of the high school juniors on the mathematical portion of the test?

Debbie scored 71 points on her history test. The mean was 65 points and the standard deviation was 3 points. Harry scored 85 points on his architecture test. The mean was 70 points and the standard deviation was 10 points. Who scored relatively better on their test?

ASK YOUR TEACHER   Pyramid Lake is on the Paiute Indian Reservation in Nevada. The lake is famous for cutthroat trout. Suppose a friend tells you that the average length of trout caught in Pyramid Lake is ? = 19 inches. However, a survey reported that of a random sample of 46 fish caught, the mean length was x = 18.4 inches, with estimated standard deviation s = 3.3 inches. Do these data indicate that the average length of a trout caught in Pyramid Lake is less than ? = 19 inches? Use ? = 0.05.   (A) What is the value of the sample test statistic? (Round your answer to three decimal places.)   (B) Estimate the P-value. a) P-value > 0.0010 b) 0.500 < P-value < 0.0010   c) 0.125 < P-value < 0.500 d)0.100 < P-value < 0.125 e) P-value < 0.100

Assume the test scores in your class are normally distributed with a mean of 84. You scored a 96, which is three standard deviations above the mean. The standard deviation, therefore, must be 12 4 3 6

In an Algebra class, the scores on a test are normally distributed. The middle 68% of the scores fall between 70 and 84. What are the mean and standard deviation for this data? What is the mean: What is the standard deviation

The average chef at a restaurant earns $17 an hour with a deviation of $1.75. What are the chances that someone is earning more than $20 an hour?

Suppose that the mean weight for men 18 to 24 years old is 170 pounds, and the standard deviation is 20 pounds. In each part, find the value of the standardized score (z-score) for the given weight. USE SALT (a) 206 pounds. Z = (b) 140 pounds. Z = (c) 173 pounds. Z = (d) 236 pounds. Z =

Skye High School has a total of 500 graduates.  The mean SAT score of Skye High School graduates is 947 with a standard deviation of 205.  To get into a premier college, a student must score 1000 or more.  If 60 students are selected at random, how many graduates can Skye High School expect to get into a premier college?

National park services, a bureau of the US government responsible for park management, is interested in how the scores of their park rangers today are better or worse than in the past. The cognitive test that the forest rangers take as remained the same over the last five years. Below are the scores for each year, compute the mean, median, mode, range, and standard deviation for each year. ​       ​Current Year 56, 45, 64, 75, 87, 81, 69, 81, 58, 92, 99, 95, 75, 92, 73, 83, 47, 69, 57, 74, 62, 74, 73, 100, 83   Five Years Ago 66, 78, 75, 79, 59, 74, 55, 89, 55, 79, 68, 27, 69, 95, 68, 90, 65, 79, 69, 79, 87, 86, 98, 81, 96

One hundred teachers attended a seminar on mathematical problem solving. The attitudes of twelve of the teachers were measured before and after the seminar. A positive number for change in attitude indicates that a teacher's attitude toward math became more positive. The 12 change scores are as follows: 3; 8; -1; 1; 0; 4; -3; 2; -1; 5; 4; -2 what is the standard deviation for this sample? what is the median change score? find the change score that is 2.2 standard deviations below the mean.