Download Areas Under the Standard Normal Curve

Name: _____________________________________________ Date: ____________ Period: ____________
Probability and Statistics
7.2 – Areas Under the Standard Normal Curve
Using the Standard Normal Distribution Table, calculate the area under the Standard Normal Curve and draw
the Standard Normal Curve with the area shaded in for Z.
Draw Graph of Stand. Normal Curve
1. Z
3
2. Z
3
3. Z 1.56
4. Z
5.
1 Z 1.63
6. 0.47
7.
2.28
Z
2.91 Z
8. Z
1.49
3.49
0.77
Name: _____________________________________________ Date: ____________ Period: ____________
9. Let x = red blood cell count in millions per cub millimeter of whole blood. For healthy females x has an
normal distribution with mean of 4.8 and standard deviation of 0.3.
a. What is the probability that a woman has a red blood cell count that is higher than 4.2 (x ≥ 4.2)?
b. What is the probability that a woman has a red blood cell count that is lower than 4.55 (x ≤ 4.55)?
c. What is the probability that a woman has a red blood cell count between 4.0 and 5.5 (4.0 ≤ x ≤5.5)?
10. Severs at BJ’s Restaurant are rated on their service via a secret shopper program. The average score
(on a 10 point scale) is an 8.8 with a standard deviation of 0.45.
a. What would be the minimum score possible if BJ’s in Laguna Hills wants all their servers to
score in the top 15%?
b. What would be the minimum score possible if BJ’s in Irvine wants their servers to score in the
top 6%?