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Category：Languages

I want to know if there is a math expression that I can use to find this relation between two numbers.

Some examples of the input and expected output are below:

`Input Multiple Result 4 3 3 6 3 6 8 3 6 4 4 4 12 4 12 16 5 15 `

Also, the expressions below from Wolfram Alpha show me the expected result but since they don't expand on the explanation on how to do it I can't learn from them...

You can employ modulo for this. For example, to calculate the biggest multiple of 4 that is less or equal than 13:

`13 % 4 = 1 13 - 1 = 12 `

in python, that could look like this:

`def biggest_multiple(multiple_of, input_number): return input_number - input_number % multiple_of `

So you use it as:

`$ biggest_multiple(4, 9) 8 $ biggest_multiple(4, 12) 12 `