Uses of t-distribution and and normal distribution



I came across two types of distribution the normal and t distribution.

Normal - The distribution in which the mean is 0 and the standard deviation is 1.

t- The t distribution is a probability distribution that is used to estimate population parameters when the sample size is small and/or when the population variance is unknown.

I want to know the cases in which this two distribution is used.


hello @sid100158,

The t-distribution is used in place of normal distribution when the sample size is small(n<30).
As you can see in the above figure,as sample size increase the t-distribution approaches a normal distribution.