Answer: 2.45
Step-by-step explanation:
Formula to find standard deviation:
[tex]\sigma=\sqrt{np(1-p)}[/tex]
Given : The proportion of the population of all Business Statistics I students consider statistics to be an exciting subject : p= 0.81
Sample size of randomly selected students from the entire population : n=39
Then , the standard deviation of the number of students who consider statistics to be an exciting subject =[tex]\sqrt{39(0.81)(1-0.81)}[/tex]
=[tex]\sqrt{39(0.81)(0.19)}\\\\=\sqrt{6.0021}\approx2.45[/tex]
Hence, the standard deviation of the number of students who consider statistics to be an exciting subject= 2.45
