SOLUTION: On a standard measure of hearing ability, the mean is 300 and the standard deviation is 20. Give the raw scores for persons whose Z scores for persons who score 340, 310, and 260.

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Question 888631: On a standard measure of hearing ability, the mean is 300 and the standard deviation is 20. Give the raw scores for persons whose Z scores for persons who score 340, 310, and 260. Give the raw scores for persons whose Z scores on this test are 2.4, 1.5, and -4.5.
Answer by Okamiden(22) About Me  (Show Source):
You can put this solution on YOUR website!
Z score for someone with 340 :
.
%28340-300%29%2F20+=+2
It is simply how many units of "20" the persion deviates from the mean "300". The person who scores 340 deviates two standard deviations of "20" from the mean.
Answer: 2.
If we have 310, the same logic applies: %28310-300%29%2F20+=+0.5
260: %28260-300%29%2F20+=+-2
.
.
With Z-scores, it's how many standard deviations away from the mean you are.
.
Z-score 2.4:
Take the mean and add 2.4 times the standard deviation.
300+2.4*20 = 348.
.
For the two others:
300+1.5*20 = 330
300-4.5*20 = 210
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Hope that helps. :)