Laura007 Posted January 2, 2006 Share Posted January 2, 2006 http://www.magictricks.co.uk/mindreader/MagicTricksMR Quote Link to comment Share on other sites More sharing options...
Popcorn Posted January 2, 2006 Share Posted January 2, 2006 Magic Laura Quote Link to comment Share on other sites More sharing options...
ali-s Posted January 2, 2006 Share Posted January 2, 2006 How does it know Spooky Quote Link to comment Share on other sites More sharing options...
Guest Posted January 2, 2006 Share Posted January 2, 2006 That's going to bug me till I work out how it knows......! Quote Link to comment Share on other sites More sharing options...
Trish Posted January 2, 2006 Share Posted January 2, 2006 Hubby says as a guess, only certain combinations to the puzzle will have a valid answeron the table and therefore all the valid answers will have the same symbol. Off to check it out Quote Link to comment Share on other sites More sharing options...
Trish Posted January 2, 2006 Share Posted January 2, 2006 Oooo he's too clever. Try this, when you get the screen choose 10, 20 and 30 work out those answers are obviously 9, 18 and 27. They all have the same symbol. Quote Link to comment Share on other sites More sharing options...
Lesley Posted January 2, 2006 Share Posted January 2, 2006 But I chose 33(27) and Carl chose 42(36) - different symbols I need to know how it works as well now Quote Link to comment Share on other sites More sharing options...
Lesley Posted January 2, 2006 Share Posted January 2, 2006 I've cracked it now - I can go to bed happy Quote Link to comment Share on other sites More sharing options...
Richard and Jo Posted January 3, 2006 Share Posted January 3, 2006 very good - answer will always be divisible by 9 - all have same symbol. Quote Link to comment Share on other sites More sharing options...
Trish Posted January 3, 2006 Share Posted January 3, 2006 not as clever as he thought then but on the right tracks Quote Link to comment Share on other sites More sharing options...
Trish Posted January 3, 2006 Share Posted January 3, 2006 aren't you lot a clever bunch then Quote Link to comment Share on other sites More sharing options...
Trish Posted January 3, 2006 Share Posted January 3, 2006 okay clever clogs husband now says why are they all divisible by 9. He means what's the mathamatical proof for it Quote Link to comment Share on other sites More sharing options...
Popcorn Posted January 3, 2006 Share Posted January 3, 2006 Straight over my head with all those numbers. I really thought it was magic too Quote Link to comment Share on other sites More sharing options...
Richard and Jo Posted January 3, 2006 Share Posted January 3, 2006 I have no idea but it so happens that the sum of the 2 digits of a 2 digit number when subtracted from the original number will be divisible by 9. Probably to do with using base 10? Hang on - I left school 20 years ago and uni 13 years ago so I dont care. I am happy to do my sons homework with him which involves sticking pictures beginning with the letter p in a book!! Good trick anyway which will baffle you if its only done once. Quote Link to comment Share on other sites More sharing options...
Popcorn Posted January 4, 2006 Share Posted January 4, 2006 I have no idea but it so happens that the sum of the 2 digits of a 2 digit number when subtracted from the original number will be divisible by 9. Probably to do with using base 10? eh ?????? Quote Link to comment Share on other sites More sharing options...
Richard and Jo Posted January 4, 2006 Share Posted January 4, 2006 Sorry people - just starting to talk rubbish again ready for going back to work! Quote Link to comment Share on other sites More sharing options...
Guest Posted January 5, 2006 Share Posted January 5, 2006 I still can't work it out!!! Quote Link to comment Share on other sites More sharing options...
Popcorn Posted January 5, 2006 Share Posted January 5, 2006 Don't worry Shona. Me either. Infact I didn't even understand the explanation, let alone try and work it out. We'll stick to looking pretty instead Quote Link to comment Share on other sites More sharing options...
Cate in NZ Posted January 5, 2006 Share Posted January 5, 2006 Shona, you and Gina both have a good excuse for not understanding it. All those pregnancy hormones - I'm convinced that these babies take over the brain as well as the belly Me, on the other hand Let's say that no-one's ever going to describe me as a mathematical genius I'm off to read that explanation again, maybe I'll finally get it if I concentrate hard enough Quote Link to comment Share on other sites More sharing options...
Lesley Posted January 5, 2006 Share Posted January 5, 2006 Every time you click and open up the page it has a different set of symbols for each number. The mathmatical act of subtracting the sum of two digits from the original two digit number produces a number which is divisible by 9 (don't ask me how!) So - every number which is divisible by 9 is given the same symbol and therefore it always 'knows' the answer to show. I think......... Check it by staying on the same page and writing down a few... 21 = 18 39 = 27 47 = 36 56 = 45 64 = 54 Check on all these answers on the same page - they will all have the same symbol Start again and look - all the numbers divisible by 9 will have the same symbol - but a different one to the previous page Quote Link to comment Share on other sites More sharing options...
kannie Posted January 6, 2006 Share Posted January 6, 2006 Ah. So you mean only numbers that are multiples of 9 work, and they all have the same symbol. So each time only 1 symbol will work. I think you're right - if I choose another symbol at random, it fails! So I'm not so transparent after all! Good trick all the same! Quote Link to comment Share on other sites More sharing options...
Popcorn Posted January 6, 2006 Share Posted January 6, 2006 You took the words right out of my mouth Lesley Quote Link to comment Share on other sites More sharing options...
Guest Posted January 6, 2006 Share Posted January 6, 2006 Lightbulb moment!!!!! I get it now! Thanks Lesley! Quote Link to comment Share on other sites More sharing options...
Lesley Posted January 6, 2006 Share Posted January 6, 2006 - I love numbers! Quote Link to comment Share on other sites More sharing options...
Martin Posted January 6, 2006 Share Posted January 6, 2006 Here is a simple proof that subtracting the sum of the digits of a two digit number from that number is always divisible by 9. Now, I don't want any panicking because it's algebra. And pay attention at the back there! Two digit number is always 10x+y (x is the tens, y is the units) Sum of the digits is x+y. (10x+y)-(x+y) = (9x+x+y)-(x+y) = 9x In other words, the answer is always 9 times the tens of the original number. Quote Link to comment Share on other sites More sharing options...
