3 Omani Riyal
Sultanate of Oman's official currency denoted as OMR, is on the 3rd place in this list. One Oman Riyal is equal to 2.60 US dollars and its biggest note is 50 OMR. The Central Bank of Oman officially introduces the banknotes of 100 baisa, 200 baisa, ½ rials, 1 rials, 5 rials, 10 rials, 20 rials and 50 rials.
4 Latvian Lat
Republic of Latvia has a strong currency thankfully to its well-developed infrastructure and a diversified industrial base. Lat has been the official currency of Republic of Latvia till January 2014. One unit of Latvain Lat denoted as LVL costs 1.61 US dollars. The highest note is 500 LVL, but this is rarely used.