Question

The mean gasoline consumption of 10 cars is 28 liters with a standard

deviation of 1.6 liters. Find the interval estimate using 95% confidence

interval.

Answer 1

$95\%CI=(\bar x-t_{0.025,n-1}\frac{s}{\sqrt{n}},\bar x+t_{0.025,n-1}\frac{s}{\sqrt{n}})=$

$=(28-2.26\frac{1.6}{\sqrt{10}},28+2.26\frac{1.6}{\sqrt{10}})=(26.86,29.14).$