Fix this equation by toggling just one pixel.
Saw this puzzle on Facebook and found it cute.
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- 4$\begingroup$ @bobble after answering it I've traced it back to at least seven years ago with this reddit post. But it's been reposted several times. $\endgroup$FishDrowned– FishDrowned2025-03-30 04:24:10 +00:00Commented Mar 30 at 4:24
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2 Answers
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3 Just shout the number 7
You toggle the 1 on the right-hand side into a factorial since $7! = 5040$ and $$(71 + 1)\cdot (71 - 1) = 71^2 - 1^2 = 5040$$
- 1$\begingroup$ Correct and well done. What do you mean by shout 7 though? $\endgroup$Dmitry Kamenetsky– Dmitry Kamenetsky2025-03-30 04:02:13 +00:00Commented Mar 30 at 4:02
- 9$\begingroup$ @DmitryKamenetsky Seven! 7! $\endgroup$FishDrowned– FishDrowned2025-03-30 04:19:59 +00:00Commented Mar 30 at 4:19
- 3$\begingroup$ Ok I get it now $\endgroup$Dmitry Kamenetsky– Dmitry Kamenetsky2025-03-30 04:41:27 +00:00Commented Mar 30 at 4:41
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The left hand side is $71^2-1^2=5040$, which is
$7!$, so remove one pixel from the $1$ to get $!$
