Question

question 8 of 25
a 90% confidence interval is found to be (120, 140). what is the margin of error?
a. 18
b. 10
c. 20
d. 9

Explanation:

Step1: Find interval width

Width = Upper bound - Lower bound = $140 - 120 = 20$

Step2: Calculate margin of error

Margin of error = Width / 2 = $20 / 2 = 10$

Answer:

B. 10