The average of n numbers is x̅. If 1 is added to the first number, 2 is added to the second number, 3 is added to the third number, and so on, their average becomes y. Find the value of y̅ - x̅.
1
\(\rm\frac{n +1}{2} \)
2
\(\rm\frac{n}{}\)
3
\(\rm\frac{n(n+1)}{2}\)
4
n