When the standard deviation = 0, there is no deviation at all. So the numbers are all the same. And there are seven of them. And the average is nine.
So the sample data set would just be seven 9s.
About 400 marbles. You simply set up a proportion and solve it as I did in the photo attached.
(3 x 5) x 4
3 x 5 x 4
15 x 4
60
Answer:
2.52
Step-by-step explanation:
