Posted by apryl on Wednesday, September 7, 2011 at 6:31pm.
Suppose that people's heights (in centimeters) are normally distributed, with a mean of 175 and a standard deviation of 6. We find the heights of 40 people.
(a) How many would you expect to be between 169 and 181 cm tall?
127 27
(b) How many would you expect to be taller than 170 cm?
232 32

math  PsyDAG, Thursday, September 8, 2011 at 1:09am
I don't know how you got your answers, but you answer needs to be less than 40.
Z = (scoremean)/SD
Find table in the back of your statistics text labeled something like "areas under normal distribution" to find the proportions for the Z scores. Multiply the proportions by 40.
a = proportions between the two Z scores and mean.
b = proportion in the larger portion.
Answer This Question
Related Questions
 math  Suppose that people's heights (in centimeters) are normally distributed, ...
 math  Suppose that people's heights (in centimeters) are normally distributed, ...
 Math  Suppose that people's heights (in centimeters) are normally distributed, ...
 MATH  Suppose that people's heights (in centimeters) are normally distributed, ...
 Algebra  Suppose that people's heights (in centimeters) are normally ...
 ALGEBRA  Suppose that people's heights (in centimeters) are normally ...
 algebra  Suppose that people's heights (in centimeters) are normally ...
 math  Suppose that people's heights (in centimeters) are normally distributed, ...
 Math  Suppose that people's heights (in centimeters) are normally distributed, ...
 math  Suppose that people's heights (in centimeters) are normally distributed, ...
More Related Questions