Answer to the Saturday Puzzle
On Saturday, I gave the following puzzle:
Can you make the following equation correct by moving just one number?:
45 – 46 = 1
Answer below the jump.
Short answer: no, you can’t.
Longer answer: none of the following equations are true:
- 54 – 46 = 1
- 54 = 46 = 1
- 5 – 446 = 1
- 5 – 446 = 1
- 5 – 44×6 = 1
- 5 – 464 = 1
- 5 – 464 = 1
- 5 – 46 = 41
- 5 – 46 = 14
- 5 – 46 = 14
- 4 – 546 = 1
- 4 – 456 = 1
- 4 – 45×6 = 1
- 4 – 465 = 1
- 4 – 465 = 1
- 4 – 46 = 51
- 4 – 46 = 15
- 4 – 46 = 15
- 445 – 6 = 1
- 445 – 6 = 1
- 44×5 = 6 = 1
- 454 – 6 = 1
- 454 – 6 = 1
- 45 – 64 = 1
- 45 – 64 = 1
- 45 – 6 = 41
- 45 – 6 = 14
- 45 – 6 = 14
- 645 – 4 = 1
- 465 – 4 = 1
- 46×5 – 4 = 1
- 456 – 4 = 1
- 456 – 4 = 1
- 45 – 64 = 1
- 45 – 4 = 61
- 45 – 4 = 16
- 45 – 4 = 16
You omitted the possibility of rotating the 6 to a 9.
That still leaves the same answer.
Good point. Though depending how broadly the judges are willing to interpret “move”, you could, in one fluid movement, both rotate the 6 into a 9 and turn it into an exponentiation superscript. I haven’t checked, but I’m pretty sure that raising anything to the ninth power makes it large enough that the equation still won’t hold.