1. ## Liber Abaci

Hey

I need to solve a puzzle. I don't understand much of it and can't find anything useful. Maybe someone can help me out. All I have is a hind "Liber Abaci" and the next lines:
10+5-2=59
9-6+1=
8-3=
10/5-1-2=
4*6=24
12/4+2-1=
5*6+5=
7-5=

I know the two answers for a fact, but how can 10+5-2=59 and 4*6=24 I don't understand. Maybe someone can help me find the other answers.

Thanks

2. Originally Posted by uudistaja
Hey

I need to solve a puzzle. I don't understand much of it and can't find anything useful. Maybe someone can help me out. All I have is a hind "Liber Abaci" and the next lines:
10+5-2=59
9-6+1=
8-3=
10/5-1-2=
4*6=24
12/4+2-1=
5*6+5=
7-5=

I know the two answers for a fact, but how can 10+5-2=59 and 4*6=24 I don't understand. Maybe someone can help me find the other answers.

Thanks
All I was able to find about about the "Abaci" was that it is all a matter of notation. Unfortunately I was only able to find notation for fractions, not addition or multiplication. (Though there was a section about mixed numbers, eg $2\frac{1}{3}$ was written by him as $\frac{1}{3}2$.)

You said you got two of them. If it isn't simply a matter of PEDMAS how did you get the answers? (If, for example, 5*6 + 5 = 35 and 7 - 5 = 2 then what you say may not actually be helpful, but give us what you've got.)

-Dan

Incidentally 4*6 = 24 is correct, unless again there is a notation issue...

3. Yes, 4*6=24 I did not even noticed that before. Because these have to be coordinates, then I just know that first of them has to equal 59 and fifth has to be 24. These are the degrees for the place i'm looking. Minutes and seconds are the other numbers. But still they have to be calculated with the same formula I think. But how can be 4*6= 24 and the same way 10+5-2=59