Question

The distribution of total body protein in healthy adult men is approximately Normal with mean 12.3 kg and standard deviation 0.1 kg.


What is, approximately, the probability that a randomly selected healthy man has a total body protein between 12.1 and 12.2 kg?

Answer 1

The z-scores for 12.1 and 12.2 are found from the following formula:
\[z=\frac{X-\mu}{\sigma}\]
The z-score for 12.1 is
\[z _{1}=\frac{12.1-12.3}{0.1}=\frac{-0.2}{0.1}=-2.0\]
Can you find the z-score for 12.2 ?