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Returns the confidence interval for a population mean, using a student's t distribution.

Sample Usage



The CONFIDENCE.T function syntax has the following arguments:

  • Alpha     Required. The significance level used to compute the confidence level. The confidence level equals 100*(1 - alpha)%, or in other words, an alpha of 0.05 indicates a 95 percent confidence level.

  • Standard_dev     Required. The population standard deviation for the data range and is assumed to be known.

  • Size     Required. The sample size.


  • If any argument is nonnumeric, CONFIDENCE.T returns the #VALUE! error value.

  • If alpha ≤ 0 or alpha ≥ 1, CONFIDENCE.T returns the #NUM! error value.

  • If standard_dev ≤ 0, CONFIDENCE.T returns the #NUM! error value.

  • If size is not an integer, it is truncated.

  • If size equals 1, CONFIDENCE.T returns #DIV/0! error value.

In order to use the CONFIDENCE.T formula, start with your edited Excellentable:

Then type in the CONFIDENCE.T formula in the area you would like to display the outcome:

By adding the values you would like to calculate the CONFIDENCE.T formula for, Excellentable will generate the outcome:


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