Making change, step by step
Making change is subtraction with a reason a child recognizes: you paid more than it cost, so how much comes back?
The question
Change from 10¢
price:4¢
handed over:10¢
4¢+ 6¢→10¢
4¢+ 6¢→10¢
6¢
- Two numbers matter and neither is a coin on the tray: the price, 4¢, and what was handed over, 10¢. Everything else is for afterwards.
- Count UP from the price, not down from the payment. It is one hop here: 4¢ to 10¢. Done as a take-away this is where the borrowing goes wrong; counting up there is nothing to borrow.
- That one hop IS the change: 6¢. Now find coins that make that amount.
How it works.
- 01
Two numbers matter and neither is a coin on the tray: the price, 4¢, and what was handed over, 10¢. Everything else is for afterwards.
- 02
Count UP from the price, not down from the payment. It is one hop here: 4¢ to 10¢. Done as a take-away this is where the borrowing goes wrong; counting up there is nothing to borrow.
- 03
That one hop IS the change: 6¢. Now find coins that make that amount.