In this case, we can use the z statistic to find for the proportion of students who failed the exam. The formula for z score is given as:
t = (x – u) / s
where,
x = the sample score = 60
u = sample score mean = 82
s = standard deviation = 11
Substituting all given values into the equation:
t = (60 – 82) / 11
t = - 2
Based from the standard proportion distribution tables for z, this corresponds to:
P = 0.0228
This means that 2.28% of the students failed the exam or equivalent to:
failed students = (0.0228) * 85 = 1.938
approximately 2 students failed the exam
Answer:
2 students failed the exam
Step-by-step explanation:
