Member since:
February 27, 2007

Seven Sevens

June 23, 2007 09:00 AM EDT (Updated: March 29, 2009 09:37 PM EDT)

views: 22 | rating: 10/10 (2 votes) | comments: 6

This "game" is based on the puzzle of the seven sevens. Basically, this involves starting with the sequence

7 7 7 7 7 7 7

and inserting arithmetic symbols +, -, x and/or ÷ along with any needed grouping symbols '(', ')', '[', or ']', forming an arithmetic expression.

Inserting all plus symbols (+) results in 49: 7 + 7 + 7 + 7 + 7 + 7 + 7 = 49.

For a real challenge, try forming an expression that reverses the digits (the expression resulting in 94). There is a way to get 94.

But, let's make this much easier than that. Let's try counting, starting with 0. I'll begin with an arithmetic expression that results in 0. The next person forms one that results in 1. After that, comes 2, and so forth. Let's see how far we can get with this.

(7 - 7) x (7 + 7 + 7 + 7 + 7) = 0

Tags: puzzle, arithmetic, game, sevens, math, education

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Comments: 6

Kathy D. Jun 23, 2007, 1:37pm EDT

I'm trying to wrap my mind around the one....I'll get back to you!

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carmel m. Jun 25, 2007, 10:48am EDT

hm I'm working on it. can't quite get it yet.

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Kathie D. Jul 11, 2007, 5:47pm EDT

For an answer of 1:
(7+7+7)*(7-7)+(7/7)

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Edward W. Jul 12, 2007, 4:59am EDT

[(7 + 7) ÷ 7] + 7 + 7 - (7 + 7) = 2

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Kathie D. Jul 12, 2007, 4:44pm EDT

(7+7-7)/7 + (7+7)/7 = 3

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Samantha W. Apr 9, 2009, 12:51am EDT

The 94 isn't really possible is it.... I have been trying it to do it for like ten minutes and i had to ask what my friends to and they didn't get it.. I kept getting 98 and now i hate that number.

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