Friday

August 1, 2014

August 1, 2014

Posted by **Sandra** on Sunday, July 28, 2013 at 11:37am.

Pedro took an exam in a class in which the mean was 64 with a standard deviation of 6. If his z score was +3, what was his exam score?

A students commute to school is normally distributed with a mean of 31 min and a standard deviation of 7 min. What is the probability that the student gets to school in 17 to 31 min?

Are the formulas the same for these?

And last one I need help with this:

Assume a normally distributed set of test scores with a mean of 100 and a standard deviation of 20. Find the probability that a person selected at random will have a score of the following:

a-between 60 and 140

b-less than 60

THANK YOU! I just need to know how to solve please.

- statistics -
**PsyDAG**, Sunday, July 28, 2013 at 12:22pmEquations are the same.

Z = (score-mean)/SD

For the second one, find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportion/probability related to the Z scores.

For the last problem, use the same equation and table.

**Related Questions**

stats - Relatively speaking, which statistics exam did you do better on? On ...

Statistics - In Professor Smith's statistics course, the correlation between ...

statistics - Suppose that the mean score of an exam was 77 when taken 30 ...

statistics - Suppose that the mean score of an exam was 77 when taken 30 ...

Analytical Skills - If your score on a statistics exam was 76 and the professor ...

statistics - say that you have a distribution of exam scores with a mean of 57 ...

statistics - In one history class, 34 students took an exam. The mean of the ...

statistic of behavioral science - for each of the following, identify the exam ...

Statistics - The next three questions refer to the following situation. Data ...

Statistics - 1) A Motor Company has purchased steel parts from a supplier for ...