How many business students must be randomly selected to estimate the mean monthly earnings of business students at one college? We want 95% confidence that the sample mean is within $130 of the population mean, and the population standard deviation is known to be $557.

Respuesta :

Answer:

Number of business students=71

Step-by-step explanation:

Formula:

Sample Mean= z*(Standard Deviation/[tex]\sqrt{n}[/tex])

where:

n stands for number of business students

z has different values for different Confidence. List is given below:

Confidence                   z

90%                             1.645                        

92%                             1.751

95%                             1.96

We will use z=1.96 corresponding to 95% Confidence

130=1.96*(557/[tex]\sqrt{n}[/tex])

n=(1.96*557/130)^2

n=70.52≅71

So  number of business students is 71.