Question

explain T - ratios...........................​

Answer 1

In statistics, the t-statistic is the ratio of the departure of the estimated value of a parameter from its hypothesized value to its standard error. ... For example, it is used in estimating the population mean from a sampling distribution of sample means if the population standard deviation is unknown.

Answer 2

When you perform a t-test, you're usually trying to find evidence of a significant difference between population means (2-sample t) or between the population mean and a hypothesized value (1-sample t). The t-value measures the size of the difference relative to the variation in your sample data.