For a certain exam,a score of 86 was 7 standard deviations below mean and a score of 90 was 3 standard deviations above mean.What was the mean score for the exam?
Answers.
A) 86.25
B) 84
C) 85
D) 88.8
E) 80
Mean-7SD=86   Mean+3SD=90   By solving above equations we get,   SD (absolute value)=0.4   Mean=88.8   ANS. 88.8
<result>D</result>
For a certain exam,a score of 86 was 7 standard deviations below mean and a score of 90 was 3 standard deviations above mean.What was the mean score for the exam?