Answer:
I would have to say A) 32 + 45 + 39: 3
Step-by-step explanation:
This is because when finding the average of literally anything, you want to add up all the numbers, and then divide the sum of it by the numbers you added up.
for instance: 32 + 45 + 39 = 116. now, we need to divide by 3 because we added 3 numbers up.
116 divided by 3 = x
x is our average cost per books.
hope this helped, gl on your test!! :')
The standard deviation of a sample is proportional to 1/√N where N is the sample size. In this case we are decreasing N by half, so we can write:
1/√(N/2) = √2 / √N
If we say that our standard deviation is proportional to 1/√N, the difference that occurred from decreasing the sample size by half resulted in an increase in the standard deviation by a factor of √2.
Therefore, the standard deviation is multiplied by √2.
63
5+4=9
9*7=63
Hope this helps