- 1,016

- 3

**1. The problem statement, all variables and given/known data**

Find the sum of all the four digit numbers that can be formed with the digits 0,1,2,3

**2. Relevant equations**

**3. 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?