What are the steps for least common multiple?

Answer 1

We want to express any number as multiples of numbers under 10, and as close to 0, if possible. The number 13, for example, can't be divided any more. It is called a Prime number. So a number like 26, which is reduced to 2 x 13, is as far as you can go.

2. A number is divisible by 2 if its right-hand digit is even.

3. A number is divisible by 3 if the sum of its digits is divisible by 3. For example, the digits of the number 6,561 add to produce the sum 18. Since 18 is divisible by 3, we know that 6,561 is divisible by 3.

4. A number is divisible by 4 if the number formed by the two right-hand digits is divisible by 4. For example, the two right-hand digits of the number 3,524 form the number 24. Since 24 is divisible by 4, we know that 3,524 is divisible by 4.

5. A number is divisible by 5 if its right-hand digit is 0 or 5.

6. A number is divisible by 6 if it is even and the sum of its digits is divisible by 3. For example, the sum of the digits of 64,236 is 21, which is divisible by 3. Since 64,236 is also an even number, we know that it is divisible by 6.

7. No short method has been found for determining whether a number is divisible by 7.

8. A number is divisible by 8 if the number formed by the three right-hand digits is divisible by 8. For example, the three right-hand digits of the number 54,272 form the number 272, which is divisible by 8. Therefore, we know that 54,272 is divisible by 8.

9. A number is divisible by 9 if the sum of its digits is divisible by 9. For example, the sum of the digits of 546,372 is 27, which is divisible by 9. Therefore we know that 546,372 is divisible by 9.