0
56 = 7 × 8, thus the number must be divisible by both 7 and 8 - check for each of these digits:
8 is easy to check: add the units digit to twice the tens digit to 4 times the hundreds digit; if this sum is divisible by 8 then so is the original number.
There is no easy check for 7. One I can offer:
Split the number into blocks of 3 digits starting at the right hand end.
Now alternatively subtract and add the each of the digits from the blocks: the units, tens and hundreds digits separately.
Finally add the sum of the units digits to 3 times the sum of the tens digits to twice the sum of the hundreds digits; if this sum is divisible by 7, then so is the original number.
eg 123456789 → 123 456 789
→ sum units: 9 - 6 + 3 = 6
→ sum tens: 8 - 5 + 2 = 5
→ sum hundreds: 7 - 4 + 1 = 4
→ check sum: 6 + 3×5 + 2×4 = 29
29 is not divisible by 7, so 123456789 is not divisible by 7.
[The remainder of 29 divided by 7 is 1, so 123456789 divided by 7 has a remainder of 1.]
eg is 135792648 divisible by 56?
8 + 2×4+4×6 = 40 which is divisible by 8, so 135792648 is divisible by 8.
135792648 → 135 792 648
→ sum units: 8 - 2 + 5 = 11
→ sum 10s: 4 - 9 + 3 = -2
→ sum 100s: 6 - 7 + 1 = 0
→ chk: 11 + 3×-2 + 2×0 = 5 not divisible by 7, so 135792648 is not divisible by 7
Thus 135792648 is not divisible by 56
eg is 63592648 divisible by 56?
Divisible by 8 as before: 8 + 2×4 + 4×6 = 40 = 5×8
63 592 648
→ sum units: 8 - 2 + 3 = 9
→ sum 10s: 4 - 9 + 6 = 1
→ sum 100s: 6 - 5 = 1
→ chk: 9 + 3×1 + 2×1 = 14 = 2×7 → divisible by 7
→ 63592648 is divisible by 56
(63592648 = 113558×56)
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Who invented the divisibility rules?
Jason Delaware
How can the divisibility rules help us simplify fractions?
i think divisibility rules help with fractions because it helps you reduce the fraction to make i a simple fraction.
What numbers 2 3 5 9 divides into 123456789 evenly using divisibility rules?
3 and 9. And they divide into 123456789 whether or not you use divisibility rules!
Reduce 324/711 using divisibility rules?
0.4557
324/711 reduce using divisibility rules?
0.4557
How is understanding factors help you write divisibility rules?
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
What are the divisibility rules of all prime numbers?
The divisibility rules for a prime number is if it is ONLY divisible by 1, and itself.
Who invented the divisibility rules?
Jason Delaware
What are the 2-10 divisibility rules?
12
What are reasons of using the disivility rules?
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.
How can the divisibility rules help us simplify fractions?
i think divisibility rules help with fractions because it helps you reduce the fraction to make i a simple fraction.
Which factor of 4587 uses divisibility rules?
Three
What numbers 2 3 5 9 divides into 123456789 evenly using divisibility rules?
3 and 9. And they divide into 123456789 whether or not you use divisibility rules!
Who invented 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.
What are the divisibility rules for 1 through 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
What is the divisibility rule for 21?
For any practical purpose, it is easier to simply divide, instead of looking for fancy divisibility rules. However, you can apply the divisibility rules for 3 and for 7. This works because (a) their product is 21, and (b) these numbers are relatively prime.
Is 963 divisible by 3 according to the rules of divisibility?
Yes.
