How do you figure out if one number goes into another number?

Answer 1

All numbers will 'go into' all other numbers, just sometimes they will go in, say 0.12323287555 times. I assume you mean when the second number can be divided by the first, producing an integer as the result. Let's call the first number x and the second number y.

Our equation is y/x=i, "i" representing any integer. y is always a multiple of x.

If x is 1, y is any whole number.

If x is 2, y is any even number.

If x is three, then y is any number where if you add all the digits together, then add all the digits of the result, etc. until you get a one digit number, and that number is 3, 6 or 9, the first three number of the three times table.

If x is four, then divide the second number by two. If you get an even number, then your original second number can be y.

If x is 5, y is any integer which has a 5 or 0 in the unit column.

If x is 6, y is any number where the rule for three applies after halving it.

If x is 7, I have no idea how to work out possible values of y, other than that they are multiples of 7.

If x is 8, y is any number that is even when halved and halved again.

If x is 9, y is any number which three 'goes into' once it has been divided by three.

If x is 10, y is any integer with a 0 in the units column.