An infinite population has a mean of 73 and a standard devia

An infinite population has a mean of 73 and a standard deviation of 31. A sample of size 121 is taken at random from this population. The standard error of the sample mean equals:

Solution

Standard Error= sd/ Sqrt(n)
Where,
sd = Standard Deviation
n = Sample Size

Standard deviation( sd )=31
Sample Size(n)=121
Standard Error = ( 31/ Sqrt ( 121) )
= 2.82