Step 1 :The problem is asking for the probability that the sample mean cholesterol level is between 187 and 193. To solve this, we can use the properties of the normal distribution.
Step 2 :The sample mean follows a normal distribution with mean equal to the population mean and standard deviation equal to the population standard deviation divided by the square root of the sample size.
Step 3 :We can standardize the values 187 and 193 to z-scores using the formula \(Z = \frac{X - \mu}{\sigma / \sqrt{n}}\), where \(X\) is the sample mean, \(\mu\) is the population mean, \(\sigma\) is the population standard deviation, and \(n\) is the sample size.
Step 4 :For \(X = 187\), the z-score is \(Z_1 = \frac{187 - 199}{39.8 / \sqrt{107}} = -3.1188\).
Step 5 :For \(X = 193\), the z-score is \(Z_2 = \frac{193 - 199}{39.8 / \sqrt{107}} = -1.5594\).
Step 6 :We then use the cumulative distribution function (CDF) of the standard normal distribution to find the probabilities. The probability that the sample mean is between 187 and 193 is the difference between the CDF values at 193 and 187.
Step 7 :The CDF value at \(Z_1 = -3.1188\) is \(P_1 = 0.0009\).
Step 8 :The CDF value at \(Z_2 = -1.5594\) is \(P_2 = 0.0594\).
Step 9 :The probability that the sample mean cholesterol level is between 187 and 193 is \(P = P_2 - P_1 = 0.0594 - 0.0009 = 0.0585\).
Step 10 :Final Answer: The probability that the sample mean cholesterol level is between 187 and 193 is \(\boxed{0.0585}\).