Fifty
From Wikipedia, the free encyclopedia.

50 (fifty) is the number following forty-nine and preceding fifty-one.

50
Cardinal	fifty
Ordinal	fiftieth
Numeral system
Factorization
Roman numeral	L
Binary	110010
Hexadecimal	32

Mathematics

It is the smallest number that can be written as the sum of two squares in two distinct ways: 50 = 1² + 7² = 5² + 5². It is also the sum of three squares, 50 = 3² + 4² + 5².

Other fields

Fifty is:

• The atomic number of tin.
• The number of states in the USA (since 1959, still true in 2004)
• A calibre of ammunition (0.50 inches: see .50 BMG)
• In millimeters, the focal length of the normal lens in 35mm photography.
• the percentage equivalent to one half, so that "fifty-fifty" is commonly used for something divided equally in half, or an event of probability one half
• In U.S. dollars, the denomination of the Federal Reserve note with Ulysses S. Grant's portrait, the denomination of the savings bond with George Washington's portrait, and the denomination of treasury bonds with Thomas Jefferson's portrait.
• In cents of the U.S. dollar, the denomination of the coin with John F. Kennedy's portrait.
• In years of marriage, the gold wedding anniversary.
• part of the name of 50 Cent, a rapper.
• The year AD 50.

49 and 51

The original article can be found at: http://en.wikipedia.org/wiki/Fifty.
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