11-39. Suppose X1, . . . ,Xn depicts random sample drawn from an exponential probability density f (x; λ) = λe−λx, x > 0,λ > 0. It can be demonstrated that a 100(1−α)% confidence interval for λ has the form (1, 2) =

χ2

α/2 2n¯x ,

χ2 1−(α/2)

2n¯x

. Given this result, let us assume that a random sample has been drawn from an exponential probability density with unknown λ. If

ni

=1 xi = 23, 250, determine a 95% confidence interval for λ.