SOLUTION: The mean grade of Adrian in the final examination in Mathematics was 85 and the standard deviation was 7. In Science, his mean grade was 89 and the standard deviation was 13. He sc

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Question 1190987: The mean grade of Adrian in the final examination in Mathematics was 85 and the standard deviation was 7. In Science, his mean grade was 89 and the standard deviation was 13. He scored 90 in Mathematics and 94 in Science. In which subject was his standing higher?
Answer by ikleyn(52803) About Me  (Show Source):
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The mean grade of Adrian in the final examination in Mathematics was 85 and the standard deviation was 7.
In Science, his mean grade was 89 and the standard deviation was 13. He scored 90 in Mathematics and 94 in Science.
In which subject was his standing higher?
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Use the formula for z-score


    Z = %28x+-+mu%29%2Fsigma


where


Z	=	standard score
x	=	observed value
mu	=	mean of the sample
sigma	=	standard deviation of the sample


So, in Math     Z%5Bmath%5D    = %2890+-+85%29%2F7 = 5%2F7.    


    In Science, Z%5Bscience%5D = %2894+-+89%29%2F13 = 5%2F13.  


His score in Math,  5%2F7,  is higher than his score in Science,  5%2F13.      ANSWER

Solved.