Test your problem solving skills!

mp3duck · 20 Jun 2011 at 14:14

OK, done!
Trust sent!

that was fun way to test the grey matter during my lunch break!

Vonhelmet · 20 Jun 2011 at 14:17

Figured it out now. I'll email a solution later.

Angilion · 20 Jun 2011 at 14:25

That was interesting. I limited myself to using only notepad, to see if I could do it with just logic. I suspect there is a more elegant solution than the one I came up with.

Morbius · 20 Jun 2011 at 14:26

23JMZ07 said:
I think it can be done with algebra but there are lots of equations to do! Compared to T&E which is relatively quick

You'd use matrices. Even then, you've not got enough information to solve it outright. You need to apply some logic at the end.

Devrij · 20 Jun 2011 at 14:30

I've worked out plenty of substitutions for all the equations, but as of the last few minutes haven't actually managed to set one up to solve for one particular variable. Clearly my brain is getting soft!

Morbius · 20 Jun 2011 at 14:30

Greebo said:
You sure? I make it 9 equations if you think about it ...............

And there is an obvious 10th equation sat there as well.

I think I have the obvious 10th equation that you speak of, but I don't see how you get nine equations from the table. Four rows and four columns make eight, but one of the rows is the same as one of the columns, so you're left with just seven.

mp3duck · 20 Jun 2011 at 14:35

where was the puzzle from btw?

Aero · 20 Jun 2011 at 14:39

Good puzzle was fun for 20 mins or so. Barely used half a page of A4, mind you I did most of it in my head.

jas72 · 20 Jun 2011 at 14:41

Greebo said:
Ah trial and error

I didn't even use/look at the grid. I just wrote the equations out and crossed out the duplicate. 1st column, 1st row and 3rd column gave me three letters right off. After that it was easy.

lol of course ... you can tell I've been out of school for 22 years

Greebo · 20 Jun 2011 at 14:42

Morbius said:
I think I have the obvious 10th equation that you speak of, but I don't see how you get nine equations from the table. Four rows and four columns make eight, but one of the rows is the same as one of the columns, so you're left with just seven.

Ah sorry my mistake. 7 equations from the grid plus another obvious one made up from the fact that each letter is an unique number from 1 to 9.

I solved it by logic anyway but from 3 equations its easy to work out what 3 numbers are so that would then leave you 7 equations and 6 variables so you could then solve the rest by simultaneous equations.

Morbius · 20 Jun 2011 at 15:06

Greebo said:
Ah sorry my mistake. 7 equations from the grid plus another obvious one made up from the fact that each letter is an unique number from 1 to 9.

OK, that's what I got! I thought I'd just checked in case I was going mad (which is entirely possible).

Although using logic is much quicker

Cat_In_Pyjamas · 20 Jun 2011 at 15:12

Pretty clever puzzle. Had to assume to values of two symbols at one stage, but that assumption proved to be correct as all other numbers then fell perfectly into place.

sbi5ar · 20 Jun 2011 at 15:18

Cat_In_Pyjamas said:
Pretty clever puzzle. Had to assume to values of two symbols at one stage, but that assumption proved to be correct as all other numbers then fell perfectly into place.

I came upon this and there is a solution which means it no longer becomes an assumption but fact...

You probably did it a lot quicker than me though just going on an assumption

Greebo · 20 Jun 2011 at 15:22

sbi5ar said:
I came upon this and there is a solution which means it no longer becomes an assumption but fact...

You probably did it a lot quicker than me though just going on an assumption

Yeah I got to the same bit and I thought it could be one of three numbers but saw that in fact it couldn't if you thought about it and could only be one.

Would have been quicker to try all 3 than work it out.

Vonhelmet · 20 Jun 2011 at 15:31

You can do it entirely with logical steps, no assumptions needed so no blind alleys.

fuzzy · 20 Jun 2011 at 16:36

Ax=b.

Martynt74 · 20 Jun 2011 at 16:44

I got there in the end, however mine was from general trial and error and took about 20 mins.

wilko49 · 20 Jun 2011 at 19:39

Greebo said:
Yeah I got to the same bit and I thought it could be one of three numbers but saw that in fact it couldn't if you thought about it and could only be one.

Would have been quicker to try all 3 than work it out.

I know the bit you mean - I started working all 3 out, but saw that I didn't need to.