Question

If n=16, x¯(x-bar)=37, and s=6, find the margin of error at a 80% confidence level

Answer 1

Solution :

Given that,

= 37

s =6

n =16

Degrees of freedom = df = n - 1 = 16 - 1 = 15

At 80% confidence level the t is ,

= 1 - 80% = 1 - 0.80 = 0.20

  / 2= 0.20 / 2 = 0.10

t /2,df = t0.10,15 = 1.341 ( using student t table)

Margin of error = E = t/2,df * (s /n)

= 1.341* ( 6/ 16)

= 2.01