was
equal to the population mean 
. In this case, the sample mean of 580 does not
equal the population mean (555) therefore, Z = 0.0 is an incorrect answer.Based on the formula below, the only way to obtain a z value equal to 0.0 would
be if the sample mean was
equal to the population mean . In this case, the sample mean of 580 does not
equal the population mean (555) therefore, Z = 0.0 is an incorrect answer.
