Scores obtained by students in an advanced placement test has a mound shaped (normal)distribution with a mean of 70 and a standard deviation of 10. the approximate proportion of students whose scores are above 90 points is close to
To evaluate the proportion of students who scored over 90 points will evaluated as follows: P(x>20)=1-P(z<Z) where: z=(x-μ)/σ where: x=90 μ=70 σ=10 z=(90-70)/10 z=2 P(z<2)=0.9772 hence P(x>90)=1-0.9772=0.0228
