Divisibility Rule of 7: Rule, Examples

Divisibility Rule of 7

A number is divisible by 7 if, when we double the last digit and subtract it from the rest of the number, the result is a multiple of 7 (like 0, 7, 14, 21, etc.).

If the new number is still big, we can repeat the steps until we get a small number we can check easily.

Steps to Check Divisibility by 7

1. Take the last digit of the number.

2. Double it. (Multiply it by 2)

3. Subtract this number from the rest of the number.

4. If the result is a multiple of 7 or becomes 0, then the number is divisible by 7

 

Examples

Example 1: Is 203 divisible by 7?

1. Take the last digit: 3

2. Double it: 3 × 2 = 6

3. Subtract from the rest of the number: 20 - 6 = 14

4. 14 is a multiple of 7 (14 ÷ 7 = 2)

203 is divisible by 7.

 

Example 2: Is 364 divisible by 7?

1. Take the last digit: 4

2. Double it: 4 × 2 = 8

3. Subtract from the rest of the number: 36 - 8 = 28

4. 28 is a multiple of 7 (28 ÷ 7 = 4)

364 is divisible by 7.

Try It Yourself:

Are they divisible by 7?

1. 574
2. 133
3. 945