The test statistic for the one-sample t-test can be found by using either technology or the formula shown below, where SE Subscript EST is the estimated standard error, x overbar is the sample mean, mu 0 is the value of the parameter that the null hypothesis says is true, s is the sample standard deviation, and n is the sample size. tequalsStartFraction x overbar minus mu 0 Over SE Subscript EST EndFraction , where SE Subscript ESTequalsStartFraction s Over StartRoot n EndRoot EndFraction