Answer:
The total number of samples that give this outcome is 5.
Step-by-step explanation:
Since Y takes values in {0,1,2,3}, For us to have that 
implies that all of them are zero but one. The one that is non-zero necessarily is equal to 1. To calculate the number of samples that give this outcome is equivalent to counting the total number of ways in which we can pick the i-index such that 
. Note that in this case we can either choose Y1 to be 1, Y2 to be 1 and so on. So, the total number of samples that give this outcome is 5.
The answer is: Find the mean of the differences with the other numbers in the set<span>. Add the squared differences and then divide the total by the number of items in </span>data<span> in your </span>set; t<span>ake the square root of this mean of differences to </span>find<span> the standard </span>deviation.
You solve this, you simply divide 32 by 4 to find out how many you can buy. If you divide 32 by 4, you get 8. So you can buy 8 train tickets in total.
