>Well then there is the case of the blind person getting a ride to the ATM and not wanting to tell the driver what his pin number is so he uses the Braille keypad to enter his pin number... but he has gota trust someone cause the 20's and 1's are the same size...
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Jumping in w/o knowing the whole story sorry. Surprisingly though they can differentiate 20's and 1's better than me. And more they can differentiate an imitation much much better than me just by touching. IOW I'm kinda blind at what I can see :)
In our currency 100,000 and 10,000,000 (go figure how much they're in $:) are very close in color to human eye and no commas between 0s making it difficult to read at a glance. Sometimes mistakenly I can give one in place of other. If I give smaller in place of bigger seller thinks I'm trying my chance to cheat him, and on the other I might cheat myself depending on seller :( Their size differ but I'm not of course sensitive to size.
Cetin