A) 74
B) 76
C) 78
D) 80
E) 82
The correct answer should be A.
Thanks in advance!
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We can set up two equations with two unknowns to solve this problem.adi wrote:For a certain examination, a score of 58 was 2 standard deviations below the mean, and a score of 98 was 3 standard deviations above the mean. What was the mean score for the examination?
A) 74
B) 76
C) 78
D) 80
E) 82
The correct answer should be A.
Thanks in advance! :D
If we let x = mean and s = standard deviation, then a score of 58 that was 2 standard deviations below the mean would mean 58 = x - 2s. Similarly, a score of 98 that was 3 standard deviations above the mean would mean 98 = x + 3s.adi wrote:For a certain examination, a score of 58 was 2 standard deviations below the mean, and a score of 98 was 3 standard deviations above the mean. What was the mean score for the examination?
A) 74
B) 76
C) 78
D) 80
E) 82