Question

1. The table below shows data on a subsample of participants in the 7th examination of the Framingham Offspring Study.

Characteristic	n	Sample Mean	Population Standard Deviation
Systolic Blood Pressure	10	121.2	11.1
Diastolic Blood Pressure	10	71.3	7.2
Total Serum Cholesterol	10	202.3	37.7
Weight	10	176.0	33.0
Height	10	67.175	4.205
Body Mass Index	10	27.26	3.10

Which of the following is the approximate margin of error for the 95% confidence level for Diastolic Blood Pressure

a. 0.03

b. 0.14

c. 4.5

d. 5.9

Answer 1

sample mean, xbar = 71.3
sample standard deviation, σ = 7.2
sample size, n = 10

Given CI level is 95%, hence α = 1 - 0.95 = 0.05
α/2 = 0.05/2 = 0.025, Zc = Z(α/2) = 1.96

ME = zc * σ/sqrt(n)
ME = 1.96 * 7.2/sqrt(10)
ME = 4.5

Option c) is answer