Math Is Fun Forum

coolcat23

Member

Registered: 2006-06-21

Posts: 553

I need help!!!

I need help on the following question:
  place numbers1-9 on the lines so that all the equations are accurate

     
      __ divided by  _ = _ - _ = _ + _ = _ x _

                          PLEASE HELP!!!!!!!!!!!!!!!!!!!

---

The world revolves around me. Deal with it.

luca

Guest

Re: I need help!!!

just try it out-

__ divided by  _ = _ - _ = _ + _ = _ x _

1,2,3,4,5,6,7,8,9

its impossible, ill proove it by exhaustion

lets just stick to the division and multiplication

the division will always be <= 9, (max / min = 9) and has to be an integer to satisfy the rest of the equalities

(im changing order to division = multiplication = addition = subtraction)

9/1 = fail (can only do 3x3, but cant do that, using same number)
8/1 = 4x2 = 2+6 = fail (cannot use 9-1, 1 is used)
8/1 = 4x2 = 3+5 = fail (cannot use 9-1, 1 is used)
7/1 = fail (can only do 7x1, both are taken)
6/1 = 3x2 = fail (cannot get an addition with other numbers)
5/1 = fail (can only do 5x1, both are taken)
4/1 = fail (can only do 4x1, both taken, or 2x2, but thats same number)
3/1 = fail (can only do 3x1, both are taken)
2/1 = fail (can only do 2x1, both are taken)

9/3 = fail (can only get 3 using 3)
8/4 = 2x1 = fail (cannot get 2 = 1+1, same number, and 1 is already taken anyways)
8/2 = 4x1 = fail (cannot do 1+3, 1 is taken, 2+2 is using same number 3 times)
6/3 = 2x1 = fail (cannot get 2 = 1+1, same number, and 1 is already taken anyways)
6/2 = 3x1 = fail (can only get 3, using 3)
4/2 = fail (can only get 2 using 2)

Ricky

Moderator

Registered: 2005-12-04

Posts: 3,791

Re: I need help!!!

There aren't any solutions if you include 0, either.

---

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

Ricky

Moderator

Registered: 2005-12-04

Posts: 3,791

Re: I need help!!!

The first solution that exists for starting at 1 is when the highest number is 13:

10 / 1 = 13 - 3 = 4 + 6 = 2 * 5

---

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

Ricky

Moderator

Registered: 2005-12-04

Posts: 3,791

Re: I need help!!!

Weirdly enough, that's the same for starting at 0.

---

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

coolcat23

Member

Registered: 2006-06-21

Posts: 553

Re: I need help!!!

I've got it! I think.After a couple of hours trying different things i got this:.

56 divided by 8 = 9 - 2 =3 + 4 =1 x7

---

The world revolves around me. Deal with it.

Ricky

Moderator

Registered: 2005-12-04

Posts: 3,791

Re: I need help!!!

Oh, is that what the double underscore was for?  Well that changes everything.

---

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

Ricky

Moderator

Registered: 2005-12-04

Posts: 3,791

Re: I need help!!!

And that is a unique solution.  i.e. there aren't any others.

---

"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

luca-deltodesco

Member

Registered: 2006-05-05

Posts: 1,470

Re: I need help!!!

Oh, is that what the double underscore was for?  Well that changes everything.

i was wondering why there was 9 numbers, but 8 places for them

oh, and if you didnt notice, 'luca' is me, when i post, and then realise im not logged in and cant be math to

edit no2

what the? a r * e d, is converted to math?!

Last edited by MathsIsFun (2006-06-27 09:42:14)

---

The Beginning Of All Things To End.
The End Of All Things To Come.

MathsIsFun

Administrator

Registered: 2005-01-21

Posts: 7,713

Re: I need help!!!

Yeah, coz itz a bit rooood.

---

"The physicists defer only to mathematicians, and the mathematicians defer only to God ..."  - Leon M. Lederman

coolcat23

Member

Registered: 2006-06-21

Posts: 553

Re: I need help!!!

Thanks for all your help!!
                        

---

The world revolves around me. Deal with it.