Question

4. The following intervals were plausible population proportions for a given sample. Find the margin of error in each case.

Answer 1

Answer: a. 0.15  b. 0.03 c. 0.055 d. 0.05

Step-by-step explanation:

For plausible intervals of population proportions , the margin of error is basically half of the difference between upper limit and lower limit.

a.  Interval =  From 0.35 to 0.65

Upper limit = 0.65

Lower limit = 0.35

Difference = Upper limit- Lower limit

= 0.65-0.35=0.30

Margin of error = (Difference)÷2  =(0.30)÷2=0.15

b. Interval =  From 0.72 to 0.78

Upper limit = 0.78

Lower limit = 0.72

Difference =  0.78-0.72 = 0.06

Margin of error  =(0.06)÷2=0.03

c. Interval =  From 0.84 to 0.95

Upper limit = 0.95

Lower limit = 0.84

Difference =0.95-0.84= 0.11

Margin of error = (0.11)÷2 = 0.055

d.Interval =  From 0.47 to 0.57

Upper limit =  0.57

Lower limit =  0.47

Difference = 0.57-0.47=0.10

Margin of error = (0.10)÷2=0.05