F-Test Two-Sample for Variances Self-Service Checkout Sales Employee Operated Checkout Sales Mean 36,709.11 46,995.93 Variance 56,649,037.54 401,208,905.56 Observations 180.00 180.00 df 179.00 179.00 F 0.14 P(F<=f) one-tail - F Critical one-tail 0.78 f-test to analyse whether the variances among th groups are equal