Finding a number that can divide evenly into another number?

[jim1174]

Main Question or Discussion Point

when you have two numbers and you need find a number can can divide evenly into both is there an easy method to do this

 

[jedishrfu]

Are you thinking of the greatest common denominator?

 

[SteamKing]

when you have two numbers and you need find a number can can divide evenly into both is there an easy method to do this

There are some rules which can lessen the amount of work involved:
1. Even numbers are all evenly divisible by 2.
2. Numbers ending in 0 or 5 are also divisible by 5 or multiples of 5.
3. If the sum of the digits in a number can be divided evenly by 3, then the original number can also be divided by 3. For example, if n = 522, then 5 + 2 + 2 = 9, which is divisible by 3 evenly; therefore 522 is also evenly divisible by 3. (522/3 = 174)

 

[lurflurf]

Yes it is called the Euclidean algorithm.

http://en.wikipedia.org/wiki/Euclidean_algorithm

 

[HallsofIvy]

Are you thinking of the greatest common denominator?

Since there are no fractions involved here, you must mean "greatest common divisor". In fact there is no "greatest common denominator" for a set of fractions- there is the "least common denominator" which is a number into which all the denominators will divide.

 

[jedishrfu]

Since there are no fractions involved here, you must mean "greatest common divisor". In fact there is no "greatest common denominator" for a set of fractions- there is the "least common denominator" which is a number into which all the denominators will divide.

Yes, you are right. I was thinking GCD and my memory brought up the wrong term. Thanks for the correction. I should have added a reference and then I would have caught my mistake.