Found this puzzle as a translation question. The Chinese is fairly simple, it just asks to solve for the ? in the bottom right square.
The actual puzzle though, I have no clue about. Can any of you solve it?
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Sign up to join this communityFound this puzzle as a translation question. The Chinese is fairly simple, it just asks to solve for the ? in the bottom right square.
The actual puzzle though, I have no clue about. Can any of you solve it?
After spending too much time on this, even forgetting how algebra works at one point, here are the only two relations I found that might serve as answers:
The (top * bottom) - (left + right) == 40 in the three completed boxes.
(5*13)-(5+20) = 40
(4*12)-(5+3) = 40
(4*16)-(4+20) = 40
(5*11)-(7+?) = 40
? = 8
The sum of the numbers inside the outer circle is 68, for the outside sum to be equivalent, ? must be 2. I also noticed that when ? is 2, the sums of the diagonal insides and diagonal outsides form alternating pairs of 23 and 45:
7+5+13+20 = 45 and 5+5+11+2 = 23
4+4+3+12 = 23 and 20+16+4+5 = 45
We have...
...group (block) sums $$\begin{matrix}43 & 24 \\ 44 & 23 + x\end{matrix}$$ If we set $x=0$, we get $$\begin{matrix}43 & 24 \\ 44 & 23 \end{matrix}$$ Going through them in the way they are arranged (in the circle), we get last digit $434343...$ and and first digit $224422...$ This is a pretty regular pattern if you ask me... ;-)
Of course, there are several simple relations which also could be regarded as answers.
I think that
$? = 4$
Because
In the upper left square, the bottom triangle-value squared ($13^2$) subtracted by the left triangle-value squared ($5^2$) makes $$13^2 - 5^2 = 12^2.$$ In the upper right square, the right triangle-value squared ($5^2$) subtracted by the top triangle-value squared ($4^2$) makes $$5^2 - 4^2 = 3^2.$$ Now for the bottom left and bottom right squares, we reverse it. For the bottom left square, we do $$\text{(left triangle)}^2 - \text{(bottom triangle)}^2\tag1$$ (notice that before we did bottom triangle $-$ left triangle) and for the bottom right square, we do $$\text{(top triangle)}^2 - \text{(right triangle)}^2\tag2$$ (notice that before we did right triangle $-$ top triangle). We do this because they make squared numbers. Solving for $(1)$, we have $$4^2 - 4^2 = 0^2$$ and for $(2)$, we need $$5^2 - ?^2 = x^2$$ for some number $x$. Let's rewrite the equation as $$5^2 = x^2 + ?^2$$ and we can see that either $x = 3$ and $? = 4$ or $x = 4$ and $? = 3$. Which one is it? Well the upper left square has two $5$'s and the upper right has one $5$. So this means that if the bottom left square has two $4$'s, then the bottom right must also have one $4$. And since none of the triangle-values in the bottom right square are $4$, then we have that $$? = 4$$ (and $x = 3$).