# statistics

A score that is 10 points below the mean corresponds to a z-score of z=-2.00. What is the population standard deviation?

1. 👍
2. 👎
3. 👁
1. If z = -2, the score is 2 standard deviations below the mean. It is also 10 points below the mean.

-2*sigma = -10

The standard deviation (sigma) is therefore 5.

1. 👍
2. 👎

## Similar Questions

1. ### Statistics

IQ test scores are normally distributed with a mean of 100 and a standard deviation of 15. Find the x- score that corresponds to a z-score of 2.33.

2. ### statistics

A score that is 6 points below the mean corresponds to a z-score of z= - .50, what is the population standard deviation?

3. ### Math

For a population with a standard deviation of s = 12, a z-score of z = +0.50 corresponds to a score that is above the mean by 6 points.​ True or False

4. ### algebra

Chase scored 14 points on Monday, and he doubled his score each day thereafter. How many points did he score on Thursday? A. 224 points B. 112 points C. 56 points D. 42 points Thanks :)

1. ### Math

Suppose you have a mean standardized score of 1500 points with a standard deviation of 150 points. This data is normally distributed. What is the z-score of 1600 points? 0.75 0.5 0.67 0.32

2. ### Math

For a class test, the mean score was 65, the median score was 71 and sthe standard deviation of the scores was 7. The teacher decided to add 5 points to each score due to a grading error. Which of the folloiwng must be true for

3. ### statistic

The average score on a standardized test is 750 points with a standard deviation of 50 points. If 2,000 students take the test at a local school, how many students do you expect to score between 700 and 800 points?

4. ### Statistics

Across the USA, results for these exams are normally distributed. What does that mean and why is this the case? If you were to create a histogram of all GRE scores, what would you expect the histogram to look like? Would it be

1. ### statistics

In a population of exam scores, a score of X = 48 corresponds to z = +1.00 and a score of X = 36 corresponds to z = -0.50. Find the mean and standard deviation of the population.

2. ### Statistic in Social Science

The verbal part of the Graduate Record Exam (GRE) has a mean of 500 and a standard deviation of 100. Use the normal distribution to answer the following questions: a. If you wanted to select only student at or above the 90th

3. ### Statistics

The Graduate Record Examination (GRE) has a combined verbal and quantitative mean of 1000 and a standard deviation of 200. Scores range from 200 to 1600 and are approximately normally distributed. For each of the following

4. ### Stats: need help please

two golfers plan to enter a tournament where the score will be determined as a team score. golfer x has a mean score of 85.4 and St. Deviation of 3.2 while golfer y has a mean score of 89.6 and St. deviation of 4.1. what is their