A five digit number is formed using digits 1, 3, 5, 7 and 9 without repeating any one of them. What is the sum of all such possible numbers?

- 6666666
- 6666600
- 6666660
- 6666000

**Answer**

If you assume that any digit is in fixed position, then the remaining four digits can be arranged in 4! = 24 ways.

So, each of the 5 digit will appear in each of the five places 24 times. So, the sum of the digits in each position is 24(1+3+5+7+9) = 600

The sum of all such numbers will be 600(1 + 10 + 100 + 1000 + 10000) = 6666600

**The correct option is B.**