Question

When constructning a confidence interval, the t-distribution is used when
1. The sample size is provided
2. The population variance is given
3. The sample variance is given
4. The question is to calculate the 95% confidence interval of the mean
5. The level of significance is 1%, 5%, 10%

Answer 1

Solution :

3. t-distribution is used when sample variance is given.

It is used when the variance of of the population is unkown