What is the biggest common multiple of 394 and 8?

Answer 1

There is no biggest common multiple; any multiple you state as the biggest, I can add their lowest common multiple and get an even bigger common multiple.

There is only the Lowest (or Least) Common Multiple or the Highest (or Greatest) Common Factor.

The Lowest Common Factor of any set of numbers is 1.

The Highest Common Multiple does not exist (as previously explained).

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Please re-ask you question which which you meant (HCF or LCM), and PUT SPACES between the numbers as commas are stripped from questions running them into a single number. ie I have no way of knowing whether the 394 was 394 or 3,49 or 3,4,9 or 34,9 which will lead to a difference answer. Please write them with spaces, ie 34, 9 or 3, 4, 9 or 34, 9 (note the SPACES after the commas).

Answer 2

There cannot be any such thing as a "biggest common multiple". Once you find the least common multiple (LCM) of a set of numbers, you can keep adding the LCM to itself over and over again. Each new number you get will be a common multiple of your set of numbers, but each new number will always be larger than the previous. This means that you can keep adding while the number approaches infinity and you will still never find a greatest multiple.