The class mean score on a test was 80, and the standard deviation was 15. If Jack's score was within 2 standard deviations of the mean, what is the lowest score he could have received?  Answers:
A) 30  B) 31  C) 50  D) 90  E) 89
1 SD from the mean is ADDING and Subtrating the amount if standard deviation from the mean one time. 2 SD from the mean is ADDING and Subtracting TWICE.   1SD from the mean ranges from 95 to 65, where 95 is within SD above the mean and 65 within 1SD below the mean   2SD=15 TWICE=30 from the the mean, which is 95 to 50, where 90 is within 2 SD above the mean AND 50 is within 2 SD below the mean.   Answer = 50
<result>C</result>
The class mean score on a test was 80, and the standard deviation was 15. If Jack's score was within 2 standard deviations of the mean, what is the lowest score he could have received?