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xI Reverend Ix
14-07-2008, 09:35 PM
A short legend, then a problem for you to solve.

When the creator of the game of chess showed his invention to the ruler of the country, the ruler was so pleased that he gave the inventor the right to name his prize for the invention. The man, who was very wise, asked the king this: that for the first square of the chess board, he would receive one grain of wheat, two for the second one, four on the third one and so forth, doubling the amount each time. The ruler, who was not strong in math, quickly accepted the inventor's offer, even getting offended by his perceived notion that the inventor was asking for such a low price, and ordered the treasurer to count and hand over the wheat to the inventor. However, when the treasurer took more than a week to calculate the amount of wheat, the ruler asked him for a reason for his tardiness. The treasurer then gave him the result of the calculation, and explained that it would be impossible to give the inventor the reward. The ruler then, to get back at the inventor who tried to outsmart him, told the inventor that in order for him to receive his reward, he was to count every single grain that was given to him, in order to make sure that the ruler was not stealing from him.See if you can work this old math problem out with a pen and paper.

The wheat and chessboard problem is a mathematical problem with the following idea: Say that you have a chessboard in front of you. If you were to place a grain of wheat on the first square, two on the second, four on the third, eight on the fourth and so on, each time doubling the amount of grains, how many grains of wheat would you need to cover the entire board?



http://i249.photobucket.com/albums/gg201/reverendroyale/chess16-2.gif


You can look on the net but that won't be very FUN! the closest to it will win a king size mars bar @ XL when i turn up, have fun.:D

DinnyHoon
14-07-2008, 10:34 PM
If I have it right, then it should be 1.84467441 × 10^19

If it's a trick question, then I have no idea.

Renegade
15-07-2008, 06:29 AM
I know the answer - it was my maths GCSE coursework at school. I'm not going to reveal it as it wouldn't be fair :)

Innes
15-07-2008, 10:00 PM
If I have it right, then it should be 1.84467441 × 10^19

If it's a trick question, then I have no idea.

Yeah you're right. It's the binomial series:

S64=[1(1-2^64)/1-2]

= 1.84467441 × 10^19

Infidel
15-07-2008, 10:18 PM
Pen and Paper people!

1+2+4+8+16+32+64+128+256+512+1024+2048+4096+8192+1 6384+32768+..........

DinnyHoon
15-07-2008, 11:24 PM
Yeah you're right. It's the binomial series:

S64=[1(1-2^64)/1-2]

= 1.84467441 × 10^19

Yup :D

xI Reverend Ix
16-07-2008, 07:20 PM
well DinnyHoon you get a mars bar, KING SIZE.

18,446,744,073,709,551,615.

is the long number.

xI Reverend Ix
16-07-2008, 07:24 PM
Not too sure if anyone is interested, but if so here is another on.

One day, a person went to horse racing area, Instead of counting the number of human and horses, he instead counted 74 heads and 196 legs. Yet he knew the number of humans and horses there. How did he do it, and how many humans and horses are there?

This one will be for a Star bar.

Innes
16-07-2008, 07:35 PM
Say each horse has two legs: 196 -2*74 = 48. That 48 should be the 2 legs left over (4 legs on a horse), 48/2 = 24 horses. Take that away from 74 and you get 50 humans.

xI Reverend Ix
16-07-2008, 07:40 PM
you got it innes i thought it would take a bit longer.

Hope your goin to XL, because you have got a Star bar with your name on it Innes.

Innes
16-07-2008, 09:41 PM
Nah, unfortunately I can't go to this XL. Hell I'm still an XL Virgin, I'm always skint. I don't want to make an empty promise and say I'll be at the next one, because chances are I won't.

But, when funds allow, I'll be there in a flash.

DinnyHoon
17-07-2008, 01:22 AM
well DinnyHoon you get a mars bar, KING SIZE.

18,446,744,073,709,551,615.

is the long number.

Awesome, but I'm not going to XL :p Give it to Liam, it'll confuse the hell out of him :D

RaideR
17-07-2008, 09:48 AM
hehe :D its a good question, and people have the "proper answer down" i would think imo, but the silly answer is you try to fit that many grains or rice on a chess board :P

if a grain of rice ways 0.01 of a gram lets say :P how heavy will the rice be.

well 18,446,744,073,709,551,615 / 100 so 184467440737095516.15 grams

which in Kilograms is (184467440737095516.15 / 1000) = 184467440737095.51615


So i ask you can this rice cover a chess board, not without crushing it :D and stacking rice!