Brain Teasers
Macy Reject
A man was shopping at Macy's one very beautiful day. He bought a very expensive perfume for his wife and paid with a $100 bill. The cashier put a pen to the bill, made a black mark, then told the man that the bill was invalid. How did the cashier know the bill was fake?
Answer
The pen was a counterfeit detector that most cashiers have. It contains Lugols solution in it that turns dark purple/black when it comes in contact with starch. All paper has starch in it, except the paper that US paper bills are made out of (to prevent counterfeiting).Hide Answer Show Answer
What Next?
View a Similar Brain Teaser...
If you become a registered user you can vote on this brain teaser, keep track of which ones you have seen, and even make your own.
Solve a Puzzle
Comments
That was a good teaser
Nice facts
Nice facts
um... wha?
Very easy teaser.
I finally got one right! But I thought it was because he was paying with MONOPOLY $
I knew the answer, but I never knew just how those pens work. Huh!
well i knew that cashires had theese pens because i'v seen them use , so it was really easy for me but otherwise it was fun
very clever teaser!
that is weird but good teaser never knew that
I would've never known that.
dont the pens turn red
it was a good one it make me think for a min.
it was a good one it make me think for a min.
Duh.
i like pie
Easy but fun. I didn't know how those tricky pens work - thanks for the interesting info.
This was too easy.
I've worked w/ money so much I didn't even have to think twice. I've used those pens a lot. If it was real, it would have just been a light yellowish ink from the same pen. Very neat how unique our money is
does that mean that there are now lots of notes running around america covered in ink? i thought it was a crime to deface money...
saying that you cant deface money is for when you mark it up for no reason, but for checking for counterfeit money you only need a small mark just enough so u can see if its black or yellow, which isn't much of a mark
I work with money daily and I have one of these pens (although I never use it) so I knew the answer but WAY TO GO for making it a fun teaser!
Hey not fair, i want one of those too...
Great teaser. I had no idea but, i'm glad i managed to learn something. Keep them coming!
Great teaser. I had no idea but, i'm glad i managed to learn something. Keep them coming!
I used to work at a bank, so I knew that one. But I never knew how the pens warked, even though I used them all the time. BTW if the bill is valid, the mark is barely visible. If it's a fake, it is immediately taken out of circulation, so there won't be a lot of black marks on it.
To post a comment, please create an account and sign in.
Follow Braingle!