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add all digits in a number together over and over until you can't anymore and if that's divisible by three the whole number is divisible by three.
eg: is 324 divisible by three? let's find out. 3+2+4=? 3
2
+4
___
9
and since 9 is divisible by three so is 324.
same rule applies with 9.
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How do you know if a number is divisible by 2 and 3?
If a number is even, it's divisible by two. If the digits of a number add up to a multiple of 3, it's a multiple of 3. For example, 342 is divisible by 3 because 3 + 4 + 2 = 9 and 9 is divisible by 3.
What is the converse of the sentence A number divisible by 9 is also divisible by 3?
If a number is not divisible by 3 then it is not divisible by 9.
Is 32643 divisible by both 3 and 9?
To check for divisibility by 9 sum the digits of the number and if this sum is divisible by 9 then so is the original number. For 32643: 3 + 2 + 6 + 4 + 3 = 18 which is divisible by 9 so 32643 is divisible by 9. As 9 = 3 × 3, any number divisible by 9 is also divisible by 3, thus as 32643 is divisible by 9 it is also divisible by 3. However, for completeness: to check for divisibility by 3 sum the digits of the number and if this sum is divisible by 3 then so is the original number. For 32643: 3 + 2 + 6 + 4 + 3 = 18 which is divisible by 3 so 32643 is divisible by 3.
What is a number in between 500 and 1000 that is divisible of 3 and 9?
There are many numbers between 500 and 1000 divisible by 3 and 9. Any number divisible by 9 is divisible by 3. How about 900?
What largest 3 - digit number divisible by both 6 and 9?
999 is divisible by 9, but not by six; the next lower number divisible by 9 is 990, which is also divisible by 6, so that's the answer. Some shortcuts for divisibility: 0 is divisible by any number. If the last digit of a number is divisible by 2, the number itself is divisible by 2. If the sum of the digits of a number is divisible by 3, the number itself is divisible by 3. If the last TWO digits of a number are divisible by 4, the number itself is divisible by 4. If the last digit of a number is divisible by 5, the number itself is divisible by 5. If a number is divisible by both 2 and 3, it is divisible by 6. If the last THREE digits of a number are divisible by 8, the number itself is divisible by 8. If the sum of the digits of a number is divisible by 9, the number itself is divisible by 9. 990: 9+9+0=18, which is divisible by 9, so 990 is divisible by 9. 18 is also divisible by 3, so 990 is divisible by 3, and since 990 ends in 0 it's also divisible by 2, meaning that it's divisible by 6 as well.
How can you know a number is divisible by 3?
add all the digits of the number and check if it is divisible by 3. eg-3321=3+3+2+1=9=divisible by three.the same works for 9.
How do you know if a number is divisible by 2 and 3?
If a number is even, it's divisible by two. If the digits of a number add up to a multiple of 3, it's a multiple of 3. For example, 342 is divisible by 3 because 3 + 4 + 2 = 9 and 9 is divisible by 3.
What is the converse of the sentence A number divisible by 9 is also divisible by 3?
If a number is not divisible by 3 then it is not divisible by 9.
Can a number be divisible by 9 and 3?
Yes, any number divisible by 9 is also divisible by 3.
Is 342 disvisibel by 9?
yes, you know that because if you add the digits together and that number is divisible by 9, then that large number is divisible by 9. 3+4+2 is 9, which is divisible by 9. conclusion 342 is divisible by 9.
Is every number that is divisible by 9 divisible by 3?
Yes, every number that's divisible by 9 is divisible by 3
How do you tell if a number is divisible by 3?
If the sum of the digits can be divided by 3. 93 is divisible by 3 because 9+3=12 we know 12 is divisible by 3 because 1+2=3 so the number is divisible by 3.
Is 32643 divisible by both 3 and 9?
To check for divisibility by 9 sum the digits of the number and if this sum is divisible by 9 then so is the original number. For 32643: 3 + 2 + 6 + 4 + 3 = 18 which is divisible by 9 so 32643 is divisible by 9. As 9 = 3 × 3, any number divisible by 9 is also divisible by 3, thus as 32643 is divisible by 9 it is also divisible by 3. However, for completeness: to check for divisibility by 3 sum the digits of the number and if this sum is divisible by 3 then so is the original number. For 32643: 3 + 2 + 6 + 4 + 3 = 18 which is divisible by 3 so 32643 is divisible by 3.
What is a number in between 500 and 1000 that is divisible of 3 and 9?
There are many numbers between 500 and 1000 divisible by 3 and 9. Any number divisible by 9 is divisible by 3. How about 900?
What largest 3 - digit number divisible by both 6 and 9?
999 is divisible by 9, but not by six; the next lower number divisible by 9 is 990, which is also divisible by 6, so that's the answer. Some shortcuts for divisibility: 0 is divisible by any number. If the last digit of a number is divisible by 2, the number itself is divisible by 2. If the sum of the digits of a number is divisible by 3, the number itself is divisible by 3. If the last TWO digits of a number are divisible by 4, the number itself is divisible by 4. If the last digit of a number is divisible by 5, the number itself is divisible by 5. If a number is divisible by both 2 and 3, it is divisible by 6. If the last THREE digits of a number are divisible by 8, the number itself is divisible by 8. If the sum of the digits of a number is divisible by 9, the number itself is divisible by 9. 990: 9+9+0=18, which is divisible by 9, so 990 is divisible by 9. 18 is also divisible by 3, so 990 is divisible by 3, and since 990 ends in 0 it's also divisible by 2, meaning that it's divisible by 6 as well.
What number is divisible by 9 but not divisible by 3?
It is impossible since 3 can already go into 9.
What is the number n where if the sum of the digits of the number is divisible by n the number itself is divisible by n?
3 and 9. 93 has a digit sum of 12, initially, which is divisible by 3, but not by 9. So 93 is divisible by 3, but not by 9. 99 has a digit sum of 18, initially, which is divisible by 3 and 9. So 99 is divisible by both 3 and 9.
