Borders vs. Amazon, notes on rounding

To get results to nearest penny, you need to consider how rounding is done.

In Borders, they calculate the discount, round it, then subtract from original price. Then they figure tax on the discounted price (original minus discount) and round that, then add.

This procedure may make a difference of one penny compared to other procedures.

Hint: Borders is the best deal. It isn't even close.