SOLUTION: If the mean is 60 and the standard deviation is 7, what proportion of the scores is between 45 and 78?

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Question 370712: If the mean is 60 and the standard deviation is 7, what proportion of the scores is between 45 and 78?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi,

*Note: z+=+%28x+-+mu%29%2Fsigma

z = 78-60/7 = 2.571  NORMSDIST(2.571)  = .99493

z = 45-60/7 = -2.143 NORMSDIST(-2.143) = .01606

.99493 - .01606 = 97.89 % of the scores will be between 45 and 78