If S21 and S22 represent the variances of random samples of

If S²₁ and S²₂ represent the variances of random samples of of size n1 = 12 and n2 =8 taken from normal populations with equal variances

b) Find P[S²₁/S²₂] < 4.89

Solution

Hello!

Ok, this is the way:

    P(S21/S22)<4.89

= P ( S21/ 2 S22/ 2 < 4.89 )

This becomes a distribution F. Then:

= P(F < 4.89) = 0.99, where F has 7 and 11 degrees of freedom.