The difference betweenthe sum of the digits in odd positions andthe sum of the digits in even positionsis divisible by 11.
12
1000 times 1000 is divisible by 2, 4, 5, 8 and 10.
Three
Divisibility rules have been developed and refined by mathematicians over the centuries. It is difficult to attribute the invention of divisibility rules to a specific individual. However, some early rules can be traced back to ancient civilizations like the Egyptians, Babylonians, and Greeks. These rules were further expanded upon and formalized by various mathematicians throughout history.
1: Every number is a multiple of 1 2: The number ends in 0, 2, 4, 6 or 8 3: The sum of the digits is a multiple of 3 4: The last 2 digits are a multiple of 4 The 10s digit is even and the last digit is 0, 4 or 8 The 10s digit is odd and the last digit is 2 or 6 5: The number ends in 0 or 5 6: The number is a multiple of 2 and 3 at the same time 7: The difference between twice the last digit and the rest of the number is a multiple of 7 8: The last 3 digits are a multiple of 8 The 100s digit is even and the last 2 digits are a multiple of 8 The 100s digit is odd and the last 2 digits are 4 times an odd number 9: The sum of the digits is a multiple of 9 10: The number ends in 0 11: The difference between the last digit and the rest of the number is a multiple of 11 12: The number is a multiple of 3 and 4 at the same time 13: The sum of 4 times the last digit and the rest of the number is a multiple of 13 14: The number is a multiple of 2 and 7 at the same time 15: The number is a multiple of 3 and 5 at the same time 16: The last 4 digits are a multiple of 16 The 1,000s digit is even and the last 3 digits are a multiple of 16 The 1,000s digit is odd and the last 3 digits are 8 times an odd number 17: The difference between 5 times the last digit and the rest of the number is a multiple of 17 18: The number is a multiple of 2 and 9 at the same time 19: The sum of twice the last digit and the rest of the number is a multiple of 19 20: The number ends in 00, 20, 40, 60 or 80 21: The difference between twice the last digit and the rest of the number is a multiple of 21 22: The number is a multiple of 2 and 11 at the same time 23: The sum of 7 times the last digit and the rest of the number is a multiple of 23 24: The number is a multiple of 3 and 8 at the same time 25: The number ends in 00, 25, 50 or 75 26: The number is a multiple of 2 and 13 at the same time 27: The difference between 8 times the last digit and the rest of the number is a multiple of 27 28: The number is a multiple of 4 and 7 at the same time 29: The sum of thrice the last digit and the rest of the number is a multiple of 29 30: The number is a multiple of 3 and 10 at the same time 31: The difference between thrice the last digit and the rest of the number is a multiple of 31 32: The last 5 digits are a multiple of 32 The 10,000s digit is even and the last 4 digits are a multiple of 32 The 10,000s digit is odd and the last 4 digits are 16 times an odd number 33: The sum of 10 times the last digit and the rest of the number is a multiple of 33 34: The number is a multiple of 2 and 17 at the same time 35: The number is a multiple of 5 and 7 at the same time 36: The number is a multiple of 4 and 9 at the same time 37: The difference between 11 times the last digit and the rest of the number is a multiple of 37 38: The number is a multiple of 2 and 19 at the same time 39: The sum of 4 times the last digit and the rest of the number is a multiple of 39 40: The last 3 digits are a multiple of 40 The 100s digit is even and the last 2 digits are 00, 40 or 80 The 100s digit is odd and the last 2 digits are 20 or 60 41: The difference between 4 times the last digit and the rest of the number is a multiple of 41 42: The number is a multiple of 2 and 21 at the same time 43: The sum of 13 times the last digit and the rest of the number is a multiple of 43 44: The number is a multiple of 4 and 11 at the same time 45: The number is a multiple of 5 and 9 at the same time 46: The number is a multiple of 2 and 23 at the same time 47: The difference between 14 times the last digit and the rest of the number is a multiple of 47 48: The number is a multiple of 3 and 16 at the same time 49: The sum of 5 times the last digit and the rest of the number is a multiple of 49 50: The number ends in 00 or 50
It's not completely necessary to know the factors if the number ends in 1, 3, 7 or 9. You can sum or subtract a certain number of times the last digit by the rest of the number if the number ends in 1, 3, 7 or 9. However I think it's required to factorize the number if it ends in 0, 2, 4, 5, 6 or 8. Here are the divisibility rules of every number from 1 to 50 1: Every number is a multiple of 1 2: The number ends in 0, 2, 4, 6 or 8 3: The sum of the digits is a multiple of 3 4: The last 2 digits are a multiple of 4 The 10s digit is even and the last digit is 0, 4 or 8 The 10s digit is odd and the last digit is 2 or 6 5: The number ends in 0 or 5 6: The number is a multiple of 2 and 3 at the same time 7: The difference between twice the last digit and the rest of the number is a multiple of 7 8: The last 3 digits are a multiple of 8 The 100s digit is even and the last 2 digits are a multiple of 8 The 100s digit is odd and the last 2 digits are 4 times an odd number 9: The sum of the digits is a multiple of 9 10: The number ends in 0 11: The difference between the last digit and the rest of the number is a multiple of 11 12: The number is a multiple of 3 and 4 at the same time 13: The sum of 4 times the last digit and the rest of the number is a multiple of 13 14: The number is a multiple of 2 and 7 at the same time 15: The number is a multiple of 3 and 5 at the same time 16: The last 4 digits are a multiple of 16 The 1,000s digit is even and the last 3 digits are a multiple of 16 The 1,000s digit is odd and the last 3 digits are 8 times an odd number 17: The difference between 5 times the last digit and the rest of the number is a multiple of 17 18: The number is a multiple of 2 and 9 at the same time 19: The sum of twice the last digit and the rest of the number is a multiple of 19 20: The number ends in 00, 20, 40, 60 or 80 21: The difference between twice the last digit and the rest of the number is a multiple of 21 22: The number is a multiple of 2 and 11 at the same time 23: The sum of 7 times the last digit and the rest of the number is a multiple of 23 24: The number is a multiple of 3 and 8 at the same time 25: The number ends in 00, 25, 50 or 75 26: The number is a multiple of 2 and 13 at the same time 27: The difference between 8 times the last digit and the rest of the number is a multiple of 27 28: The number is a multiple of 4 and 7 at the same time 29: The sum of thrice the last digit and the rest of the number is a multiple of 29 30: The number is a multiple of 3 and 10 at the same time 31: The difference between thrice the last digit and the rest of the number is a multiple of 31 32: The last 5 digits are a multiple of 32 The 10,000s digit is even and the last 4 digits are a multiple of 32 The 10,000s digit is odd and the last 4 digits are 16 times an odd number 33: The sum of 10 times the last digit and the rest of the number is a multiple of 33 34: The number is a multiple of 2 and 17 at the same time 35: The number is a multiple of 5 and 7 at the same time 36: The number is a multiple of 4 and 9 at the same time 37: The difference between 11 times the last digit and the rest of the number is a multiple of 37 38: The number is a multiple of 2 and 19 at the same time 39: The sum of 4 times the last digit and the rest of the number is a multiple of 39 40: The last 3 digits are a multiple of 40 The 100s digit is even and the last 2 digits are 00, 40 or 80 The 100s digit is odd and the last 2 digits are 20 or 60 41: The difference between 4 times the last digit and the rest of the number is a multiple of 41 42: The number is a multiple of 2 and 21 at the same time 43: The sum of 13 times the last digit and the rest of the number is a multiple of 43 44: The number is a multiple of 4 and 11 at the same time 45: The number is a multiple of 5 and 9 at the same time 46: The number is a multiple of 2 and 23 at the same time 47: The difference between 14 times the last digit and the rest of the number is a multiple of 47 48: The number is a multiple of 3 and 16 at the same time 49: The sum of 5 times the last digit and the rest of the number is a multiple of 49 50: The number ends in 00 or 50
The divisibility rules for a prime number is if it is ONLY divisible by 1, and itself.
The difference betweenthe sum of the digits in odd positions andthe sum of the digits in even positionsis divisible by 11.
Jason Delaware
12
You can always check on the divisibility of a number by dividing it into another number. But if you know the divisibility rules, you can get that information easier and faster.
i think divisibility rules help with fractions because it helps you reduce the fraction to make i a simple fraction.
1000 times 1000 is divisible by 2, 4, 5, 8 and 10.
Three
3 and 9. And they divide into 123456789 whether or not you use divisibility rules!
Divisibility rules have been developed and refined by mathematicians over the centuries. It is difficult to attribute the invention of divisibility rules to a specific individual. However, some early rules can be traced back to ancient civilizations like the Egyptians, Babylonians, and Greeks. These rules were further expanded upon and formalized by various mathematicians throughout history.