Question

A test involving 340 men ages 20 to 24 found that their blood cholesterol levels had a mean of 181 mg/dl and a standard deviation of 44.5 mg/dl. (a) Determine the z-score, to the nearest hundredth, for one of the men who had a blood cholesterol level of 213 mg/dl. z213 = (b) The z-score for one man was -1.59. What was his blood cholesterol level? Round to the nearest hundredth. mg/dl

Answer 1

The z-score for a blood cholesterol level of 213 mg/dl is approximately 0.72, and the blood cholesterol level corresponding to a z-score of -1.59 is approximately 111.21 mg/dl.

Step-by-step explanation:

To determine the z-score for a man who had a blood cholesterol level of 213 mg/dl, use the formula: z = (X - μ) / σ, where X is the value, μ is the mean, and σ is the standard deviation. Plugging in the values, we have z213 = (213 - 181) / 44.5 = 0.7191 (rounded to the nearest hundredth).

To find the blood cholesterol level for a man with a z-score of -1.59, rearrange the formula to solve for X: X = μ + (z * σ). Plugging in the values, we have X = 181 + (-1.59 * 44.5) = 111.205 mg/dl (rounded to the nearest hundredth).