Question

Show Intro/Instruct You intend to estimate a popullon mean with a confidence interval You believe the population to have a normal distribution. Your sample size is 65. Find the critical value that corresponds to a confidence level of 98%. (Report answer accurate to three decimal places with appropriate rounding.) Kova = + Lic Points possible: 0 This is attempt 1 of 3.

need answer as fast as possible please

Answer 1

For n - 1 = 64 degrees of freedom, we have from the t distribution tables here:

P( t64 < 2.386) = 0.99

Therefore, due to symmetry, we have:
P(t64 > -2.386) = 0.99

Therefore, P( -2.386 < t64 < 2.386) = 0.98 which is the required confidence level here.

Therefore the critical values here are given as:

$t_{\alpha/2} = 2.386$

Therefore 2.386 is the required value here.