Question 1023355
Scores 30 and above occur at greater than or equal to one standard deviation above the mean.
We know 68.2% of a sample fits within one standard deviation.  Thus the part more than 1 s.d. is (1/2)(100% - 68.2%) = (1/2)(31.8%) = 15.9%
Thus all the scores at 30 or below would be
100% - 15.9% = 84.1%