Web Analytics
lcase
Answered

On a test of optimism, scores of people diagnosed with a particular disease are normally distributed with a mean of 20 and a standard deviation of 5.

What proportion of the scores are between 20 and 25? Between 25 and 30? Below 15?

Verified Answer :

\(\mathbb P(20

Since approximately 68% of any normal distribution lies within one standard deviation of the mean, and the distribution is symmetric, it follows that

\(\mathbb P(0