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# All Activity

1. Yesterday
2. ## A Simple Riddle

Nah. Generic deck.

4. ## Ranks and Files : Dominoes

I'm not quite sure what you are saying. A domino consists of 2 squares. So while there are 56 squares, there's only 28 dominoes. So for example, A2 and A3 together are a single domino. TSLF- Do you want them arranged in an 8x7 grid like the picture? That would mean some rows and columns would contain more than one of a number. Is that correct?
5. ## Cutting pizza

All cuts should be vertical and in any direction ... I only emphasized that no horizontal cut is allowed, e.g. one could possibly divide a cake with three cuts to yield 8 pieces ... 2 vertical cuts and 1 horizontal cut! (1) 125251 pieces after 500 cuts (correct) (2) 3162 cuts gives 500704 pieces (also correct) (3) Never mind the 3rd answer since I reckon that it must be infinity, although 199999 cuts as a first approximation comes very, very close! However, there will always be a remainder of either 1 or a pretty large number. Therefore, 2 remains the minimum and maximum pieces-to-cuts ratio. I cannot, though, prove this mathematically (yet)! I wasn't aware of an entry at "Mathworld"! So, my question should actually have been a straight-forward quickie!
6. ## A Simple Riddle

Well, it's outside the box, I'll give you that : )
7. ## Cutting pizza

i dont really understand the question. your picture seem contrary to your description. your picture seems to suggest you can cut in any direction, but your description suggests all cuts have to be in the same direction. i'll solve both. for lines in any direction: http://mathworld.wolfram.com/CircleDivisionbyLines.html 1/2*(n^2 +n +2), n=500; 125251 5000000 = 1/2*(n^2 +n +2) n=3162 for cuts in the same direction: each cut adds 1 new region. for 500 cuts, that 501 rejoins to get 5000000 peices 4999999 cuts are needed
8. ## Cutting pizza

Rather change "pizza" to an enormous 2D circle then! I used pizza as to eliminate any horizontal cut, but it will be a hell of a mess should one really had to cut a pizza into so many pieces!
9. ## Ranks and Files : Dominoes

Thank you Time-LSF! Good one, but ... Apology for raising this, but there is only one "double 0" and one "double 6" combination directly adjacent next to each other in the grid, although the total of 56 (7x8) matches twice the number of 28 domino pieces in a normal set! The "double 1, 2, 3, 4 and 5" are fine.

Nope

14. ## Ranks and Files : Dominoes

A double six domino set. made up of 28 domino tiles.
15. ## Ranks and Files : Dominoes

Looks like a 7x8 set?
16. ## Ranks and Files : Dominoes

Can you arrange the 6 x 6 domino set in order that all columns and rows contains 0 - 6 ?
17. ## A Simple Riddle

Nice try. Try again.
18. ## A Simple Riddle

I wouldn't bet the farm here Ace, but call.........
19. ## A Simple Riddle

Around my kind you may just find A curse, a laugh, a grin But pressure me, I'll likely snap And send away my friends. Up on deck or over it A simple one am I, But with a hand I take command Or from you I will fly.
20. Last week
21. ## Cutting pizza

Suppose you have a pizza being cut vertically with one straight cut, you'll be left with two pieces. The ratio of number of pieces to cuts in such an instance will be 2 (a whole number, i.e. no remainder). If you cut a pizza using two straight vertical cuts, you'll have four pieces left (pieces-to-cut ratio = 2, also a whole number). Cutting the pizza thrice, the maximum pieces possible is seven (pieces/cuts = 7/3 = 2.3333..., i.e. there is a remainder of 1). See attached image. Questions ... (1) What is the maximum number of pieces that one would get by cutting the pizza 500 times using only straight vertical lines (no horizontal cuts allowed)? (2) How many cuts should one make to get a maximum of at least 5 million pieces? (3) The minimum piece-to-cut ratio with no remainder is exactly 2 as indicate above. What would be the next higher number of cuts, such that the number of resulting pieces divided by the number of cuts has no remainder?
22. ## 20 RIDDLES TO TEST YOUR MATH, IQ AND THINKING SKILLS.

I do believe #3 -- What 3 positive numbers give the same result when multiplied and added together? -- is not grammatically correct. I believe the question should be -- What three positive numbers give the same result when multiplied together and when added together? The adverb should not be implying each operation occurs together, but should occur for each operation as each operation is intended to be independent, yet gives the same result. I do agree with Donald Cartmill that #12 also is not written as it should be.
23. ## I'm not a bird

I spy with my little eye something beggining with P......