- #1

- 18,823

- 8,968

What is the sum of all the numbers formed by taking each of the digits 2,3,5,6 and 8 once?

You are using an out of date browser. It may not display this or other websites correctly.

You should upgrade or use an alternative browser.

You should upgrade or use an alternative browser.

- Thread starter Greg Bernhardt
- Start date

- #1

- 18,823

- 8,968

What is the sum of all the numbers formed by taking each of the digits 2,3,5,6 and 8 once?

- #2

haha, maybe later.

- #3

jamesrc

Science Advisor

Gold Member

- 477

- 1

6399936

- #4

- 18,823

- 8,968

Originally posted by jamesrc

6399936

How'd ya get that answer?

- #5

redrogue

- 32

- 1

2 3 5 6 8

There are: (5)*(5-1)*(5-2)*(5-3)*(5-4) or 5*4*3*2*1 = 120 permutations for the above set of numbers.

One set of numbers add up to: 2+3+5+6+8 = 24.

So, the sum of all numbers formed from 120 permutations is:

120*24 = 2880.

- #6

jamesrc

Science Advisor

Gold Member

- 477

- 1

If I answered the right question, for all of the 5-digit numbers you can make, each digit appears 24 times in each column, so you can write:

24*(22222+33333+55555+66666+88888)=6399936

Edit: Oh, I thought it was the sum of the numbers made by the combinations, not the sum of their digits.

24*(22222+33333+55555+66666+88888)=6399936

Edit: Oh, I thought it was the sum of the numbers made by the combinations, not the sum of their digits.

Last edited:

- #7

- 18,823

- 8,968

Originally posted by jamesrc

If I answered the right question, for all of the 5-digit numbers you can make, each digit appears 24 times in each column, so you can write:

24*(22222+33333+55555+66666+88888)=6399936

Edit: Oh, I thought it was the sum of the numbers made by the combinations, not the sum of their digits.

James gets the point!

Here is an alternative way:

4!*(2+3+5+6+8)*(11111) = 6,399,936

Share:

- Last Post

- Replies
- 3

- Views
- 7K

- Replies
- 1

- Views
- 3K

- Replies
- 4

- Views
- 6K

- Replies
- 7

- Views
- 1K

- Last Post

- Replies
- 21

- Views
- 3K

- Last Post

- Replies
- 8

- Views
- 8K

- Last Post

- Replies
- 7

- Views
- 8K

- Last Post

- Replies
- 27

- Views
- 2K

- Replies
- 25

- Views
- 7K

- Last Post

- Replies
- 4

- Views
- 3K