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.
Take the last digit of the number.
Double it. (Multiply it by 2)
Subtract this number from the rest of the number.
If the result is a multiple of 7 or becomes 0, then the number is divisible by 7
Take the last digit: 3
Double it: 3 × 2 = 6
Subtract from the rest of the number: 20 - 6 = 14
14 is a multiple of 7 (14 ÷ 7 = 2)
203 is divisible by 7.
Take the last digit: 4
Double it: 4 × 2 = 8
Subtract from the rest of the number: 36 - 8 = 28
28 is a multiple of 7 (28 ÷ 7 = 4)
364 is divisible by 7.
Know the divisibility rule of 8 here.
Are they divisible by 7?
1. 574
2. 133
3. 945
The divisibility rule for 7 involves taking the last digit of a number, doubling it, and subtracting that result from the remaining portion of the number. If the difference is divisible by 7 (or is 0), then the original number is also divisible by 7.
As a result, (1* 2 = 2) Subtract 2 from the remaining number, which equals 44. As a result, 44 – 2 = 42. The number 42 is the sixth multiple of 7. As a result, we know that 458409 is divisible by 7.
There are 14 numbers between 1 and 100 that can be divided by 7 precisely. 7, 14, 21, 28, 35, 42, 49, 56, 63, 70, 77, 84, 91 and 98 are the numbers.