### Quiz 07 Normal Curves 7.3 • Name:

1. For the following curves A, B, and C determine the mean µ and the standard deviation σ:

CurveMean µstandard deviation σ
A
B
C

2. Pohnpei Islands Central High School students had a mean µ of 10.9 and a standard deviation σ of 5.0 on the high school level questions on the mathematics entrance test March 2005. Assume the distribution is normal for these problems.

1. __________ What is the probability a student scored below 5.9 on the mathematics entrance test?
2. __________ An 18 is a mininum pass of the mathematics entrance test. What percent of PICS students scored above 18? Hint: This one will require use of Excel.
3. __________ If 505 students took the mathematics entrance test at PICS, what number of students passed with a score above 18?
4. The probability calculated in question 2a above is the probability a student scored randomly on the mathematics entrance test. What does it mean that these students scored no better than random?

Normal Statistics
Calculate a z value from an x z = =STANDARDIZE(x, µ, σ)
Calculate an x value from a z x = σ z + µ =σ*z+µ
Find a probability p from a z value     =NORMSDIST(z)