Math Is Fun Forum

Nasir Hassan

Member

Registered: 2020-04-11

Posts: 6

Our Columbus Problem

What's wrong with this solution?!

There are Eight dots.  So 3 dots make a minus sign like in a dot matrix printer!  And 5 dots make a plus sign.  So the 7 numbers are used as follows :

570 - 496 + 8 = 82

Each of the 7 digits is used once, and the 8 dots are used.

Interested to hear your comments.

Nasir

Bob

Administrator

Registered: 2010-06-20

Posts: 10,619

Re: Our Columbus Problem

hi Nasir,

I think your solution is OK.  You could argue it's better as it only uses those digits and dots. But Sam Loyd wouldn't have paid out for it.  He'd have said "What's a dot matrix printer?"

later edit: actually it does say "add up to", so you'd have to use the minus as a negative sign (there is a subtle difference).

I've noticed that the given solution to some problems is just one of a number of possibilities.  The 'solution' page just says "our Solution" so it's implicit that other solutions may also exist. 

In the keys puzzle https://www.mathsisfun.com/puzzles/sam- … uzzle.html  I couldn't see an analytical way to get an answer so I number crunched it with a program.  And got 9 solutions

Bob

---

Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you!  …………….Bob