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You could combine the tests for divisibility by 3 and 4.
To test for divisibility by three, add all the digits together and see if they're divisible by three. If necessary, you can keep repeating the addition until you come up with a single-digit number.
To test for divisibility by four, take the last two digits. If that two-digit number is divisible by four, then the whole number is. This is because any multiple of 100 is divisible by 4, so only the last two digits matter.
Combined, these two tests will allow you to quickly check for divisibility by 12.
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Can a number be divisible by 6 and 12?
Absolutely - any number that is divisible by 12 - is also divisible by 6 !
Is 534 divisible by 9?
No. To test: add the digits together and if the sum is divisible by 9, so is the original number. The test can be repeated on the sum until a single digit remains. If this single digit is 9 then the [original] number is divisible by 9, otherwise it gives the remainder when the [original] number is divided by 9. 534 → 5 + 3 + 4 = 12 12 → 1 + 2 = 3 3 ≠ 0 so 12 is not divisible by 9 so 534 is not divisible by 9; the remainder when 534 is divided by 9 is 3.
Write a rule to determine when a number is divisible by 12?
A number is divisible by 12 if it is divisible by 3 AND it is divisible by 4. Rule 1a (Divisibility by 3): Add up all the digits of the number. Is this number divisible by 3? Rule 1b (Divisibility by 4): Is the number formed by the last two digits of the original number (the number left after deleting the hundreds, thousands, millions etc) divisible by 4? If the answer to 1a is NO, then the number is not divisible by 3 and so not divisible by 12. In this case, obviously, rule 1b is irrelevant. If the answer to 1b is NO, then the number is not divisible by 4 and so not divisible by 12. If the answer to both 1a and 1b is YES, then the number is divisible by 12.
Is the number 57 prime or composite?
You can see quickly that the number 57 is divisible by 3: 3 * 20 = 60 so if we remove one of those 3's then 3 * 19 = 57 so it is divisible by at least 3 and 19 (as well as itself and 1) Because it is divisible by numbers other than itself and one, 57 cannot be prime. You can also check to see if a number is divisible by 3 by adding its digits and checking to see if that number is divisible by 3: 5+7 = 12 ; and 12 is divisible by 3, so 57 is as well.
What is a number that is divisible by 2 through 12?
Numbers that are divisible by 2 through the number 12 are: 4, 6, 8, 10 and 12.
Can 612 divisible by 4?
612 is divisible by 4. To test divisibility by 4, if the last 2 digits of the number are divisible by 4, then the whole number is divisible by 4. Last 2 digits of 612 are 12, and 12 is divisible by 4 since 3x4 = 12, so 612 is divisible by 4. 612 / 4 = 153.
Is 4603 divisible by 3?
No.You can test the divisibility of a number by three, in the following manner.If the sum of the digits is divisible by three then the original number is also.example,Is 21 divisible by three, (yes the answer is 7)by summing the numbers 2+1 we get three which is of course divisible by itself.another; (harder)Is 1335 divisible by 3?Lets do the test.... 1+3+3+5=12 , and since 12 is divisible by three so is the original number 1335. (The answer is 445)Also this test can be continued; in the 12 above , 1+2=3 , which is divisible by 3 , and so on.So the original 4603 number,4+6+0+3=13 , which is not divisible by 3 , so 4603 is not divisible by 3 either.(also 4603 is a prime number; a number divisible by only 1 and itself)
Can a number be divisible by 6 and 12?
Absolutely - any number that is divisible by 12 - is also divisible by 6 !
What are numbers that are divisible by 6?
Numbers are divisible by 6 if they are divisible by both 2 and 3.All even numbers are divisible by 2. Odd numbers are not.To see if a number is divisible by 3, add the individual digits of the number to each other and see if that number is divisible by 3. If it is, then the original number is also divisible by 3.Example: 2712, add 2+7+1+2=12 Is 12 divisible by 3? Yes. Therefore, 2712 is divisible by 3.The number 2712 is also divisible by 2, since it is an even number.Now you know that 2712 is divisible by 6.
Is 534 divisible by 9?
No. To test: add the digits together and if the sum is divisible by 9, so is the original number. The test can be repeated on the sum until a single digit remains. If this single digit is 9 then the [original] number is divisible by 9, otherwise it gives the remainder when the [original] number is divided by 9. 534 → 5 + 3 + 4 = 12 12 → 1 + 2 = 3 3 ≠ 0 so 12 is not divisible by 9 so 534 is not divisible by 9; the remainder when 534 is divided by 9 is 3.
Write a rule to determine when a number is divisible by 12?
A number is divisible by 12 if it is divisible by 3 AND it is divisible by 4. Rule 1a (Divisibility by 3): Add up all the digits of the number. Is this number divisible by 3? Rule 1b (Divisibility by 4): Is the number formed by the last two digits of the original number (the number left after deleting the hundreds, thousands, millions etc) divisible by 4? If the answer to 1a is NO, then the number is not divisible by 3 and so not divisible by 12. In this case, obviously, rule 1b is irrelevant. If the answer to 1b is NO, then the number is not divisible by 4 and so not divisible by 12. If the answer to both 1a and 1b is YES, then the number is divisible by 12.
How can you tell if a number is divisible by 12?
If a number is divisible by both three and four, it's divisible by twelve.
Is the number 57 prime or composite?
You can see quickly that the number 57 is divisible by 3: 3 * 20 = 60 so if we remove one of those 3's then 3 * 19 = 57 so it is divisible by at least 3 and 19 (as well as itself and 1) Because it is divisible by numbers other than itself and one, 57 cannot be prime. You can also check to see if a number is divisible by 3 by adding its digits and checking to see if that number is divisible by 3: 5+7 = 12 ; and 12 is divisible by 3, so 57 is as well.
How can you tell if 1234 is divisible by 7?
Divide the number by thirteen. If the answer comes out even with no remainder, the number is divisible by thirteen.
Is 12 divisible by 336?
No. 12 cannot be divisible by any number bigger than 12.
How many numbers between 201 and 301 are divisible by both 3 and 4?
To be divisible by 3 and 4 the number must be divisible by 12. 201/12 = 16.75 so the smallest number in the range, divisible by 12, is 17*12 = 204 301/12 = 25.08 so the largest number in the range, divisible by 12, is 25*12 = 300 The number of multiples of 12 is 25 - 16 = 9
Is a number divisible by 12 is divisible by both 2 and 6?
Yes, because 12 is divisible by 2 and 6.
