SOLUTION: A new drug has a 75% probability of curing a patient within one week. Suppose 38 patientsare treated using this drug. Let X be the number of patients who are cured within a week. I

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Question 1189289: A new drug has a 75% probability of curing a patient within one week. Suppose 38 patientsare treated using this drug. Let X be the number of patients who are cured within a week. I found the standard deviation as 2.67 and mean as 28.5.
Find P(x-σ < X < x + σ)
I don't understand how to find this value between the two. My book got 0.740.
Answer by math_tutor2020(3817) (Show Source):
You can put this solution on YOUR website!

You have the correct values for and approximately.

I'm assuming you meant to say I replaced the lowercase x's with mu's.

If that's what your teacher wants, then I'm not sure how your book got 0.740

According to the Empirical Rule, it should be roughly 0.68 since about 68% of the population is within 1 standard deviation of the mean. The more accurate value is roughly 0.6826894921 which unfortunately is nowhere close to 0.740

Perhaps my assumption made at the top of this page is incorrect. If it is, then please let me know.