Find the critical values
χ2L=χ21−α/2 χ L 2 = χ 1 − α / 2 2 and χ2R=χ2α/2 χ R 2 = χ α / 2 2
that correspond to 80 % degree of confidence and the sample size
n=15.
χ2L= χ L 2 =
χ2R= χ R 2 =