At Capetown college out of the 400 students taking Psychology 101 received an average score of 76 on the final exam, and the scores had a normal distribution. The bottom 16 percent of scores will receive a failing grade. If 8 students receive a score of 97 or higher, what is the score at or below which student fail the course?
a.35 b.40 c.55 d.62 e.66
Okay I dont know the answer but here is the logic I used ......i dont think its correct help me where I am wrong
Mean=76
8 Students received 97 or higher
P(x>97) = 8/400
P(X>97)=2%
100-2%=98%
Since 98% of the values in the distribution lie within 3 standard deviation of the mean
Hence
97-3(s.d)=76
s.d=7
16% failed hence (100-16%)/2 = 42%+42%= 84% which lies between 1 standard deviation or 2 standard deviation for approximation i use 2
hence
76-2*7= 62 ( I subtract cause its about failing )
what do you all say? some say answer is 66?
a.35 b.40 c.55 d.62 e.66
Okay I dont know the answer but here is the logic I used ......i dont think its correct help me where I am wrong
Mean=76
8 Students received 97 or higher
P(x>97) = 8/400
P(X>97)=2%
100-2%=98%
Since 98% of the values in the distribution lie within 3 standard deviation of the mean
Hence
97-3(s.d)=76
s.d=7
16% failed hence (100-16%)/2 = 42%+42%= 84% which lies between 1 standard deviation or 2 standard deviation for approximation i use 2
hence
76-2*7= 62 ( I subtract cause its about failing )
what do you all say? some say answer is 66?
