iNTELLIGENCE

IQ solution to: Equation without arithmetic operators

A function that converts 0 into 1 is factorial “!”. To calculate factorial, one has to multiply as follow:

n! = n×(n-1)×(n-2)×...×1, e.g. 5! = 5×4×3×2×1.
0! is a special case for which is valid: 0! = 1.

This is fine, but then we still have 1 1 1 = 6. So we fill in some pluses: 1 + 1 + 1 = 6. This way we get 3 = 6, which is much better than 0 = 6.

At least, we can do the final step: again factorial: 3! = 3×2×1 = 6.

Using 8 arithmetic operators, this is the final solution:

(0! + 0! + 0!)! = 6

Addendum: A smart reader sent me an even shorter solution which is not completely correct in terms of mathematics, but uses just 5 arithmetic operators and some imagination: put minus signs into the the first two zeros and a slash before the third zero. Add a plus and a minus sign between the numbers, and you get something that looks like 8 + 8 - 10 = 6.

Another smart reader suggested the following creative solution: if you put a slash so that it begins at the upper left side of a zero, the result does resemble a six. Therefore, by adding three slashes and a + and a -, you get the new equations 6 + 6 - 6 = 6 or 6 - 6 + 6 = 6. Even more, you can also use multiplication and division signs instead of the + and -. That is, 6 ÷ 6 × 6 = 6 and 6 × 6 ÷ 6 = 6 also work.

With all these 6, it looks a little bit diabolic, whew...

Based on this idea, the same reader created an even easier answer: convert any one of the zeros to a six using a slash, and add two plus signs. One result would be 6 + 0 + 0 = 6.

Gimme more intelligence!