In: Statistics and Probability
_______________
E = _______________
_______________< < _______________
Solution :
degrees of freedom = n - 1 = 37 - 1 = 36
a) t/2,df
= t0.10,36 = 1.306
b) Margin of error = E = t/2,df
* (s /
n)
= 1.306 * (11.2 /
37)
Margin of error = E = 2.405
c) The 80% confidence interval estimate of the population mean is,
- E <
<
+ E
12.3 - 2.405 < < 12.3 + 2.405
9.9 <
< 14.7