Its simple what you do is you subtract not divide because if you where dividing you would be putting something into groups equally and not Addison because your not trying to find how much in all so it would be Subtraction another way is to see if there is how many more or How much more so if you see that then you know that its Subtraction! Hope this helps!:)
C is the answer you're looking for
The answer is A
because there is no other answer
The complete question in the attached figure N 1
we know that
The formula for Sample Standard Deviation is indicated in the attached figure N2
n in this problem is 4 <span>and Yuri had to divide in the formula by 3 </span>
therefore
the answer is Yuri divided by n instead of n -1