Sister's math problem X-post

[Sifmole]

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I see it this way....

There is 1 way to group 7 "columns"
2 ways for 6
3 ways for 5
4 ways for 4
5 ways for 3
6 ways for 2
7 ways for 1



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This is right.


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and finally 1 big triangle

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This is the one way to group 7 columns, dont recount it.

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(((1*7)+(2*6)+(3*5)+(4*4)+(5*3)+(6*2)+(7*1))*3)+1
((7+12+15+16+15+12+7)*3)+1
((84)*3)+1
252+1
253

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Where did all this multiplication come from, there are 6 ways to group 2 so there are 6*2=12 possibilities??? NO, There are 6 you just said so.

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Uh, yeah..... [img]/images/graemlins/blush.gif[/img] whoops..... been a long day.

[Tom1975]

I think it's 84 also for trapazoids. You can't use the top row, but you can use row 2 by itself, 3 by itself, and 2&3 combined.

[ihardlyknowher]

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I think it's 84 also for trapazoids. You can't use the top row, but you can use row 2 by itself, 3 by itself, and 2&3 combined.

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Ding, ding, ding, ding, ding!!! Gutter, tell her what's she's won.

Good job guys! Now try this one:

[lucas9000]

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Blow me dildo. Nobody in 2+2 history annoys me more than you.

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Good luck in your sister's big upcoming race.





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holy crap i laughed my ass off at that.

[ghostface]

Its 84. I just counted it in 30 seconds. Count number in top row. Multiply by 3. Done. Basic math is easy.

This doesnt qualify as basic or math. It's counting.

[Worrots]

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(26!) is 26+25+24+23 etc...

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No. n! = n*(n-1)*(n-2)*...*1

It also has nothing to do with solving this problem.

[Tom1975]

While brute force counting will solve the problem, there are quicker ways to solve it mathematically. What if there had been 100 columns instead of 7?

[Wintermute]

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Blow me dildo. Nobody in 2+2 history annoys me more than you.

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Good luck in your sister's big upcoming race.





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holy crap i laughed my ass off at that.

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it gave me a boner.

[GFunk911]

It's obviously 84, but I'm really really interesting in seeing jakethebake or one of his minions graphically point out one of the hidden triangles. Will it be a trapezoid? Will it kill you in your sleep? Stay tuned!!