SOLUTION: Scores on a test have a mean of 73 and 10 percent of the scores are above 87. The scores have a distribution that is approximately normal. Find the standard deviation.
Algebra ->
Probability-and-statistics
-> SOLUTION: Scores on a test have a mean of 73 and 10 percent of the scores are above 87. The scores have a distribution that is approximately normal. Find the standard deviation.
Log On
Question 800697: Scores on a test have a mean of 73 and 10 percent of the scores are above 87. The scores have a distribution that is approximately normal. Find the standard deviation. Answer by oscargut(2103) (Show Source):
You can put this solution on YOUR website!
P(X>87)=0.1
P(Z> (87-73)/s ) = 0.1
14/s = 1.28
s = 14/1.28
s = 10.94
If you need more help with similar questions, homework, assignments, you can contact me now at:
mthman@gmail.com
Thanks