$1.10 dollar bill

John E. Franklin · 2011-02-04 05:53:18

Explain why a
dollar bill of the
value of ten cents
more ($1.10) would
simplify most
calculations for
a cashier giving
out change to the
customer who hands
her/him the funny
bill.

John E. Franklin · 2011-02-06 02:24:06

The cashier was a
tad quirky in that
she enjoyed multiplying
the digits together of
the price of the item
being purchased, then
she would tell the
customer that the
last digit of the
product of the digits
of her change would
be the same number
as the last digit of the
product of her purchase
price digits!!!!
(stick to 2-digit numbers for this)

Last edited by John E. Franklin (2011-02-06 02:28:29)

John E. Franklin · 2011-03-02 12:44:01

Note that 56 cents plus 54 cents = 110 cents.
Note that 75 cents plus 35 cents = 110 cents.
Note that 11 cents plus 99 cents = 110 cents.
And note that 110 = 10 * 10 + 10 * 1.
Since there is a ten's place and a one's place, the
change the cashier needs to give for any 2-digit
valued item is simple. Simply subtract each digit from 10!!!!
The problem with the normal one dollar bill is that,
you can do this, but then you have to reduce the tens digit by one.

plutoman · 2011-05-01 21:06:23

I think a 99 cent bill (or coin) might be more popular. Then you wouldn't end up with all those pesky pennies every time you bought something ending in .99 cents.

John E. Franklin · 2011-05-04 05:45:00

gOOD pOINT.

Math Is Fun Forum

#1 2011-02-04 05:53:18

$1.10 dollar bill

#2 2011-02-06 02:24:06

Re: $1.10 dollar bill

#3 2011-03-02 12:44:01

Re: $1.10 dollar bill

#4 2011-05-01 21:06:23

Re: $1.10 dollar bill

#5 2011-05-04 05:45:00

Re: $1.10 dollar bill

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