Comments by "Toby" (@toby9999) on "Can you solve it? – Addition wall problem" video.

  1. Yeah, I even have a mathematics degree, and I've never heard of it.
    3
  2. Yeah, there's always a super brain who does it in seconds... but what you wrote there is not a few seconds work, at least not for 99% of us.
    2
  3. Both work equally well.
    1
  4. Moving sides and changing signs is equivalent to adding or subtracting from both sides. You've just skipped the step in your head. What you did is quicker but it's easier to make a mistake that way.
    1