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The most common currency traded today is the US Dollar with almost 85% of the trading volume.
I think that the most common currency in the world is the USD (United States dollar). Or at least that's what it is in the business world. :)
The EU (European Union) is not having trouble creating a common currency. It has already created it as of 2002.
advantage and disadvantage of having common currency
See: Roman currency
If you are travelling to a country that has a different currency than your own, then it is a good idea to get some money transferred into the currency of the country you are travelling to so that you are able to buy things there.
a common nation currency
There are aspects of communism that are a good idea. There are portions of it that did not work well.
The Euro is the common European currency. It is currently used in the 13 block Euro-zone as their common currency. It is currently going down against the dollar.
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The common currency of Europe was first introduced on Jan 1, 2002
The local currency used in the Amazon rainforest depends on the country it is located in. In Brazil, the Brazilian Real is commonly used, while in Peru, the Peruvian Sol is the currency of choice. It is always a good idea to have some local currency on hand for transactions in the area.
The Euro is a controversial currency at the moment because it has been dragged down by the European debt crisis. The price of the Euro isn't at its lowest point, in fact its near its highest in two years. However, the Euro has been flirting between drops and gains over this period of economic turmoil in Europe. The idea of the Euro, a common currency, is not truly controversial in Europe, however. The idea of a common currency allows for easy trading, for example.
The currency in Bhutan is the Dzongha. I have absolutely no idea how much on dollar is in that currency.
It is the euro.
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