Step 1 :Given in the problem: sample mean (\(\bar{x}\)) = 81.2, population mean (\(\mu\)) = 77, and standard error (SE) = 0.7
Step 2 :The standardized z-test statistic is calculated using the formula: \(z = \frac{\bar{x} - \mu}{SE}\)
Step 3 :Substitute the given values into the formula: \(z = \frac{81.2 - 77}{0.7}\)
Step 4 :Calculate the above expression: \(z = \frac{4.2}{0.7}\)
Step 5 :\(\boxed{z = 6}\) is the value of the standardized z-test statistic