49 replies to this topic

[araver]

Adding another example to the challenge:

4 *&* 8 = 6
20 *&* 5 = 12
8 *&* 31 = 34
15 *&* 2 = 9
80 *&* 31 = 62
71 *&* 40 = 86
83 *&* 13 = 94
50 *&* 11 = 30
-------------
44 *&* 47 = ?

[plainglazed]

Okay - maybe time for some group think. some thoughts in the following spoiler so if you dont care to see. strictly fwiw...

Spoiler for some observations

every case except the first and including the case to solve contains a prime number. seems too much of a coincidence not to be relevant unless it's just meant to distract. have been playing with factors and combinations with no luck so far.

[Maquis]

I've been playing with this one as well, but I don't have a strong math background so most of the puzzles in this section elude me.

My thoughts added to Plainglazed:

Spoiler for

I first tried experimenting with bases, but since the last puzzles were based related, I thought this would be different. I also noticed the primes and my "gut" feeling is that the solution is related to factoring. I factored all the problems and noticed a few patterns but nothing concrete. I think I just have not gone far enough with the math.

[araver]

Adding another example:

4 *&* 8 = 6
20 *&* 5 = 12
8 *&* 31 = 34
15 *&* 2 = 9
80 *&* 31 = 62
71 *&* 40 = 86
83 *&* 13 = 94
50 *&* 11 = 30
40 *&* 42 = 28
-------------
44 *&* 47 = ?

And secretly

Spoiler for

enjoying that there there are at least three people thinking on this.
But that's not a secret anymore since you opened the spoiler

EDIT: Spelling

Edited by araver, 06 January 2011 - 07:39 PM.

[plainglazed]

Spoiler for 44 *&* 47 =

54?

[araver]

Spoiler for 44 *&* 47 =

54?

Spoiler for

No, sorry.

[araver]

Another random example (since no requests so far)

4 *&* 8 = 6
20 *&* 5 = 12
8 *&* 31 = 34
15 *&* 2 = 9
80 *&* 31 = 62
71 *&* 40 = 86
83 *&* 13 = 94
50 *&* 11 = 30
40 *&* 42 = 28
21 *&* 20 = 20
-------------
44 *&* 47 = ?

[plainglazed]

Spoiler for what I had thought

if either operand is prime subtract one. if an operand is even, divide it by its highest prime factor then multiply by its lowest prime factor (if there is a lower one). if an operand is odd, first subtract its lowest prime fractor (only have two cases thus far so maybe just subtract 3) then treat as even. finally, add the two decoded operands.

for example: 80 *&* 31 = 62 --> (80*2/5) + (31-1) = 62

This method seems to work for all the examples except the final answer. For that reason am thinking I might still be close but havent gotten anything else.

EDIT: suspect the extra manipulation of the odd operands is a little too convoluted and maybe the subtracting of one from the prime operands is too and that there is a simple single rule that works for all.

Edited by plainglazed, 08 January 2011 - 02:56 PM.

[araver]

4 *&* 8 = 6

20 *&* 5 = 12

8 *&* 31 = 34

15 *&* 2 = 9

80 *&* 31 = 62

71 *&* 40 = 86

83 *&* 13 = 94

50 *&* 11 = 30

40 *&* 42 = 28

21 *&* 20 = 20

22 *&* 12 = 14

-------------

44 *&* 47 = ?

[Darth Legion]

Spoiler for

Even a hint of a solution to this continues to elude me. Does the operation affect two digit numbers differently than single digit numbers?