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**John E. Franklin****Member**- Registered: 2005-08-29
- Posts: 3,585

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.

**igloo** **myrtilles** **fourmis**

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**John E. Franklin****Member**- Registered: 2005-08-29
- Posts: 3,585

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)*

**igloo** **myrtilles** **fourmis**

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**John E. Franklin****Member**- Registered: 2005-08-29
- Posts: 3,585

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.

**igloo** **myrtilles** **fourmis**

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**plutoman****Member**- Registered: 2008-01-06
- Posts: 27

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.

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**John E. Franklin****Member**- Registered: 2005-08-29
- Posts: 3,585

gOOD pOINT.

**igloo** **myrtilles** **fourmis**

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