Divisibility rules help determine if one number is divisible by another without performing the division. Here are the divisibility rules for numbers 1 through 10:

1. Divisibility by 1:

• Every number is divisible by 1.

2. Divisibility by 2:

• A number is divisible by 2 if the last digit is even (0, 2, 4, 6, or 8).

3. Divisibility by 3:

• A number is divisible by 3 if the sum of its digits is divisible by 3.

4. Divisibility by 4:

• A number is divisible by 4 if the last two digits form a number divisible by 4.

5. Divisibility by 5:

• A number is divisible by 5 if its last digit is 0 or 5.

6. Divisibility by 6:

• A number is divisible by 6 if it is divisible by both 2 and 3.

7. Divisibility by 7:

• A number is divisible by 7 if, after doubling the last digit and subtracting it from the rest of the number, the result is divisible by 7. This is more complicated but effective.

8. Divisibility by 8:

• A number is divisible by 8 if the last three digits form a number divisible by 8.

9. Divisibility by 9:

• A number is divisible by 9 if the sum of its digits is divisible by 9.

10. Divisibility by 10:

• A number is divisible by 10 if its last digit is 0.

Would you like more details or examples on any of these rules?

Here are five related questions:

1. What is the divisibility rule for 11?
2. How can divisibility rules be applied in large numbers?
3. Why does the sum of digits work for divisibility by 3 and 9?
4. How does the divisibility rule for 7 work with larger numbers?
5. What are the divisibility rules for prime numbers greater than 10?

Tip: Memorizing divisibility rules can speed up mental math and help in quickly checking factors during exams!