Canada. The federal government and provincial government each charge a tax which is added to items you buy. The provincial tax is added on top of the federal one usually, unless the province uses what is called Harmonized Tax which combines both.
In Quebec for example we have 5% GST (Federal) and 9.5% PST (Provincial). When you add both, with the 9.5% on top of the 5%, it takes 14.975%. So if you buy something labelled $100 CDN, you will usually pay $114.97.
There are exceptions in which case some items are charged one tax (books for example) or none (food for non-immediate consumption). Rules are very specific. For example, buying 6 food items makes them exempt from taxes because that is not considered for immediate consumption. On supermarket receipts it will be marked F, P or FP depending on which tax applied.