| Field | Education |
| Went Obsolete | 1970s |
| Made Obsolete By | Cash registers that calculated change |
| Knowledge Assumed | Ability to count |
| When useful | rarely |
To count back change, you'd take the sale amount and count UP to the amount given. For example if the sale price was $6.49 and the customer gave you a $20 note, you would count out change as 6.50 (+1�), 7.00 (+.25� coin x 2), 8-9-10 ($1 note x 3), 20 ($10 note).
Nobody in retail knows how to do this without the register doing it for them and god help you if you make up the cents to get an even amount back (blank stare).
Addendum: 02/20/08 Actually this is not obsolete. I own and operate a retail store in a small town, and require all my cashiers to count back the change for customers. We see it as both a courtesy to the customer, and a safeguard to help us prevent mistakes.
Added 02/22/08 I agree that this is not obsolete, however it's heading that way. With more people paying with cards and cashless transactions, and children not being taught or having enough opportunity to practice mental arithmetic, I can see this skill disappearing in the next few years.