If the sample mean is equal to the population mean, t =

a. the number of degrees of freedom
b. 0
c. the square root of the n
d. exactly the square root of the degrees of freedom

The correct answer is option b. "0".

Explanation:

In statistics, a t test is used to estimate the difference between the mean of two groups. The t value indicates how different the means are, if the sample mean is equal to the population mean, the t value will be equal to 0. If the t value is positive the sample mean will be higher than the population mean; while a negative t value indicates that the sample is lower than the population mean.

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