55 (number)
Natural number
From Wikipedia, the free encyclopedia
55 (fifty-five) is the natural number following 54 and preceding 56.
Mathematics
55 is composite number,[1] a Fibonacci number[2] and a Triangular number.
Transportation
In the United States, the National Maximum Speed Law prohibited speed limits higher than 55 miles per hour (90 km/h) from 1974 to 1987. The number 55 became a popular shorthand for the 55 mph speed limit. For example, a hand with a pair of fives in Texas hold'em poker is referred to as a "speed limit".[3]