Can you figure out the 3 Riddles?

Originally posted by SwissGambit
Now we have three answers: 1, 5, and infinite. I like how everyone adds their own unique assumption to Riddle #1. Here, it is that the subtracting must stop once you reach zero - no negative numbers allowed!

Originally posted by FabianFnas
Why is no negative numbers allowed?
We\'re not talking about money (see the first posting in this thread), we can subtract infinie many times, reaching negative infinity \'eventually\'.

Originally posted by SwissGambit
That was the assumption Sgt. Carpface made. My post was in response to his.

If you review earlier in the thread, you\'ll see that I agreed with Wolfgang - one may subtract 25 - 5 an infinite number of times.

Two girls with some dollars: are they working girls?

Sabrina has y dollars and Samantha has x dollars.

Sabrina gave Samantha as many dollars as Samantha started out with.

So now Sabrina has y-x and Samantha has 2x

Samantha then gave Sabrina back as much as Sabrina had left.

So now Sabrina has 2y-2x and Samantha has 3x-y

Sabrina then gave Samantha as back as many dollars as Samantha had left

So now Sabrina has 3y-5x and Samantha has 6x-2y


which left Sabrina broke and gave Samantha a total of $80.00.

Therefore we have (1) 3y-5x=0 and (2)6x-2y=80

Taking (1) we know 3y=5x and substituting into (2)18/5y-10/5y=80 then 8/5y=80 therefore y=50 and since they add up to 80 x=30 . Sabrina had $50.00 and Samantha had $30.00

I know someone posted the correct answer but don't these problems always seem to be based on simultaneous equations?