How do you check if a number can divide by 7?

Answer 1

Dividing by 7 (2 Tests)

• Take the last digit in a number.
• Double and subtract the last digit in your number from the rest of the digits.
• Repeat the process for larger numbers.
• Example: 357 (Double the 7 to get 14. Subtract 14 from 35 to get 21 which is divisible by 7 and we can now say that 357 is divisible by 7.

  NEXT TEST

• Take the number and multiply each digit beginning on the right hand side (ones) by 1, 3, 2, 6, 4, 5. Repeat this sequence as necessary
• Add the products.
• If the sum is divisible by 7 - so is your number.
• Example: Is 2016 divisible by 7?
• 6(1) + 1(3) + 0(2) + 2(6) = 21
• 21 is divisible by 7 and we can now say that 2016 is also divisible by 7.