need help on silly math problem

[Magnj]

My brother got this problem to do. He realy needs to get it done for extra credit. I can't figure it out. :fact:

" arrange one of each of the numbers 3,5,7 and 9 as well as one of each of the symbols -(minus), *(times), and +(plus) in every row and column to arrive at the answer at the end of the row/column "
http://i4.photobucket.com/albums/y132/Magnj/mathprob.jpg

thank you thank you thank you pleaaaaase help

[[XC] leviathan18]

so far i have this

7-5*3+9=15
- *
9*3+7-5=29
+ +
5*9+7-3=49
*-
3+7*5-9=41
= =
26 17

[Magnj]

Thanks! one thing though. Every column and row must have 1 of every symbol/number. So no repeating. Thanks.. im still working on it and mine is very close to yours :)

[[XC] leviathan18]

yes i realized that while ago but still thinking about this little problem having so much fun with it....

[trance565]

lol, that basically makes it an elimination problem

[Magnj]

anyone? Its due for him today ? If not please stop working on it :)...too much work unless your real bored

[pythagoras]

For extra credit tell him to inform the teacher that the problem is not solveable, unless you can use parenthesis.

The first line dosnt equal 15, you cant read a maths problem from left to right, the order of operations is important!

7-5*3+9--------Multiplication comes first then addition and subtraction s0 you have 7-15+9=1

To get 15 it must be written:

(7-5)*3+9=15

Regards

John.

[RaptorRaider]

I'm trying and I think I might be getting close; however I think the problem isn't solvable.
Though in a completely different way than pythagoras.

How can you combine the numbers 3,5,7 and 9 and get 26 or 28 as an answer?
Is it even possible to use 4 odd numbers and get even numbers?

Maybe this'll give him credit? Could it be a catch question?

[pythagoras]

Hi Raptor,

You know I was so annoyed with the first line of the problem and didnt look at the rest of it.

But your right, using * + and - with 4 odd numbers will always give an odd number.

Regards

John.

[RaptorRaider]

So you can confirm this problem is unsolvable?


That was easy. Only took me about 10 minutes. :)


One other problem I had was trying to get 57 with those numbers. Is that also impossible?

[Magnj]

Thanks guys :). Apparantly it was due today, and some of the kids came in with answers? I told him about the order of operations things(think it went over his head), but maybe he will bring that up.

[pythagoras]

These are the only numbers that can be made:

-58,-35,-15,-13,-7,1,13,17,25,29,41,49,61 and 65.

Regards

John.