The Centers for Disease Control & Prevention in Maryland reports that the mean w
ID: 3353482 • Letter: T
Question
The Centers for Disease Control & Prevention in Maryland reports that the mean weight (in pounds) for adult males aged 20 years and over is µ = 195. Assume that this distribution is normal in shape and the standard deviation = 30. Find the z score for a man with a weight of 125 pounds (that is, for X = 125). Round to the nearest tenths place if a fraction. [Note, if your calculated value is not identical to one of the values below, but within plus or minus 0.2 of an answer below, assume it’s a rounding error and select the answer that is closest to your calculated value.
+2.0
-2.0
+2.3
-2.3
the correct z score is a value not listed in alternatives “a” through “d”
Explanation / Answer
z = (x-mean)/Sigma
Z = (125-195)/30 = -70/30=-2.33
Hence, the correct answer is D (-2.3)