- #1
chaoseverlasting
- 1,050
- 3
Homework Statement
Find the sum of all the four digit numbers that can be formed with the digits 0,1,2,3
Homework Equations
The Attempt at a Solution
The total number of numbers possible is 3*4*4*4=192.
Since the lowest number we can form is 1000, and the highest is 3333, the sum of all the digits should be summation (1-3333) - summation(1-1000).
The summation is given by [tex]\frac{n(n+1)}{2}[/tex] or in this case,
[tex]\frac{3333*3334-1000*1001}{2}[/tex] which gives 5055611... which is nt the given answer. What am I doing wrong?