Search results
Results from the WOW.Com Content Network
To "cast out nines" from a single number, its decimal digits can be simply added together to obtain its so-called digit sum. The digit sum of 2946, for example is 2 + 9 + 4 + 6 = 21. The digit sum of 2946, for example is 2 + 9 + 4 + 6 = 21.
Casting out nines is a quick way of testing the calculations of sums, differences, products, and quotients of integers in decimal, a method known as long ago as the 12th century. [3] If an odd perfect number exists, it will have at least nine distinct prime factors. [4] Non-intersecting chords between four points on a circle
For divisibility by 9, this test is called the rule of nines and is the basis of the casting out nines technique for checking calculations. Digit sums are also a common ingredient in checksum algorithms to check the arithmetic operations of early computers. [ 3 ]
Main page; Contents; Current events; Random article; About Wikipedia; Contact us
3 Example's legibility. 1 comment. 4 The Examples are not very readable. 1 comment. 5 Removal of Pop Culture reference as "Unrelated" 5 comments. ... 11 Casting out ...
For example, 90% would be described as "one nine"; 99% as "two nines"; 99.9% as "three nines"; and so forth. However, there are different conventions for representing inexact multiples of 9. For example, a percentage of 99.5% could be expressed as "two nines five" (2N5, or N2.5) [ 2 ] or as 2.3 nines, [ citation needed ] following from the ...
Mathematical formulas are often algebraic, analytical or in closed form. [5] In a general context, formulas often represent mathematical models of real world phenomena, and as such can be used to provide solutions (or approximate solutions) to real world problems, with some being more general than others. For example, the formula
A sequence of six consecutive nines occurs in the decimal representation of the number pi (π), starting at the 762nd decimal place. [ 1 ] [ 2 ] It has become famous because of the mathematical coincidence , and because of the idea that one could memorize the digits of π up to that point, and then suggest that π is rational .