Question

In: Statistics and Probability

1. Kate and John recently took a standardized test. The summary statistics are reported below. Mean:...

1. Kate and John recently took a standardized test. The summary statistics are reported below.

Mean: 80

Standard deviation: 4

Kate’s score: 90

John’s score: 72

Assuming that the distribution is approximately normal, if 2,000 people took the test,

approximately how many people scored between Kate and John? (10 points)

approximately how many people scored better than Kate? (10 points)

approximately how many people scored lower than John? (10 points)

approximately how many people scored better than John? (10 points)

Expert Solution

(a)

(b)

(c)

(d)

orchestra answered 2 years ago

nn psychology students took a standardized test. The scores are summarized in the GFDT below. Scores ...

nn psychology students took a standardized test. The scores are summarized in the GFDT below. Scores Frequency 220 - 224 14 225 - 229 15 230 - 234 16 235 - 239 240 - 244 17 245 - 249 40 The scores are also described in the cumulative table shown below. Scores Frequency less than 225 14 less than 230 29 less than 235 45 less than 240 63 less than 245 80 less than 250 nn What is the...

1.I recently asked 100 middle school students to complete a statistics test. The mean score on...

1.I recently asked 100 middle school students to complete a statistics test. The mean score on the test was 30 points with a standard deviation of 5 points. The scores followed a normal distributions. Using this information, calculate the following: a. What is the probability a student earned a score of 45 points or less? P (score < 45 points) = b. What is the probability a student earned a score higher than 30 points? P(score > 30) = c....

A teacher looks at the scores on a standardized test, where the mean of the test...

A teacher looks at the scores on a standardized test, where the mean of the test was a 73 and the standard deviation was 9. Find the following z-score table Link What is the probability that a student will score between 73 and 90 What is the probability that a student will score between 65 and 85 What is the probability that a student will get a score greater than 70 What is the probability that a student will score...

1. The standardized IQ test is described as a normal distribution with 100 as the mean...

1. The standardized IQ test is described as a normal distribution with 100 as the mean score and a 15-point standard deviation. a. What is the Z-score for a score of 150? b. What percentage of scores are above 150? c. What percentage of scores fall between 85 and 150? d. What does it mean to score in the 95th percentile? e. What is the score that corresponds to being in the 95th percentile? 2. A friend wants to learn...

The test scores of Statistics are listed below, find the mean of the data set that...

The test scores of Statistics are listed below, find the mean of the data set that excluding the outliers: 75,48, 83, 55, 70, 78, 50, 52, 53, 40, 54, 60, 48, 65, 53, 47, 33, 53, 28, 50, 48,55 A. 54.35 B. 56.45 C. 61.15 D. 53.15

1. Nine students took the SAT test. Their scores are listed below. Later on, they took...

1. Nine students took the SAT test. Their scores are listed below. Later on, they took a test preparation course and retook the SAT. Their new scores are listed below. Use the Sign test to test the claim that the test preparation has no effect on their scores. Use α = 0.05. Student 1 2 3 4 5 6 7 8 9 Before 860 820 910 990 1000 930 870 1180 920 After 880 820 900 1030 1030 940 860...

In a city with three high schools, all the ninth graders took a Standardized Test, with...

In a city with three high schools, all the ninth graders took a Standardized Test, with these results: High School Mean score on test Number of ninth graders Glenwood 79 280 Central City 94 348 Lincoln High 66 151 The city's PR manager, who never took a college math class, claimed the mean score of all ninth graders in the city was 79.7 . Of course, that is incorrect. What is the mean score for all ninth graders in the...

1) Scores for a common standardized college aptitude test are normally distributed with a mean of...

1) Scores for a common standardized college aptitude test are normally distributed with a mean of 495 and a standard deviation of 108. Randomly selected men are given a Test Preparation Course before taking this test. Assume, for sake of argument, that the preparation course has no effect. If 1 of the men is randomly selected, find the probability that his score is at least 551.9. P(X > 551.9) = Enter your answer as a number accurate to 4 decimal...

Provide summary statistics for ?, ?1, ?2. In particular, what is the mean, median, and standard...

Provide summary statistics for ?, ?1, ?2. In particular, what is the mean, median, and standard deviation across your 51 observations? Report the results for two simple least-squares regression estimates: ? on ?1 and ? on ?2. For each regression, your report should include the estimate of the intercept, the estimate of the coefficient on the ? variable, as well as the standard error and P-value for each of those estimates. And in words, interpret these results. (How should we...

The summary statistics for the first chemistry test and the second chemistry test scores of 62...

The summary statistics for the first chemistry test and the second chemistry test scores of 62 students are as follows. 1st test 2nd test Sample Mean 88.63 84.44 Sample Standard Deviation 11.46 13.70 The teacher in charge of chemistry assumed a simple regression model that predicts the results of the 2nd test with the results of the 1st test, and obtained the following analysis of variance table through simple regression analysis. DF Sum of Squares Mean Square F Regression Residuals...