Question

According to a recent pol, 29 % of adults in a certain area have high levels of cholesterol. They report that such elevated levels "could be financially devastating to the regions healthcare system" and are a major concern to health insurance providers. Assume the standard deviation from the recent studies is accurate and known. According to recent studies, cholesterol levels in healthy adults from the area average about 205 mg/dL, with a standard deviation of about 25 mg/dL, and are roughly Normally distributed. If the cholesterol levels of a sample of40 healthy adults from the region is taken,What is the probability that the mean cholesterol level of the sample will be between 200 and 210

Answer 1

Answer:

Step-by-step explanation:

The mean value μ = 205  , standard deviation of population σ = 25

no of people n = 40

standard deviation of sample of 40 people = σ / √n

σ₁ = 25 / √ 40 = 3.95

probability between 200 and 205

P ( 200 < X < 205 ) = P ( Z= (210 - 205)  / 3.95  -  P ( Z= (200 - 205)  / 3.95

= P ( Z = + 1.26 ) - P ( - 1.26 )

= .8962 - .1038

= .7924

Probability is 79.24 % .