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1, 3, 7, 21.
Wiki User
∙ 10y ago
Wiki User
∙ 8y agoItself and any of its multiples.
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Example of divisibility rule for 21?
a number is divisible by 12 if the number is also divisible by both 3 and 7. You mean a number is divisible by 21 if it is divisible by 3 and 7.
Why is the number 21 composite?
Because 21 is divisible by numbers other than 1 and 21. 21 is divisible by 1, 3, 7, 21
Explain why 21 is not a prime number?
21 has factors other than 1 and itself, so it is not a prime number. For example, it is divisible by 3. (You can check this by adding the digits of the number: 2 + 1 = 3. If the sum of the digits is divisible by 3, the number is also divisible by 3.) Therefore, 21 is a composite number.
What number is divisible by 21 and 13?
Since the numbers are coprime, the answer is 21*13 = 273.
What number is even divisible by 3 and a multiple of 7?
Forty-two.
Example of divisibility rule for 21?
a number is divisible by 12 if the number is also divisible by both 3 and 7. You mean a number is divisible by 21 if it is divisible by 3 and 7.
What is divisible in 21 and 37?
There is nothing that is divisible in 37 and 21. Because 37 is a prime number. However, 21 is divisible by 3 and 7.
Is 21 a prime number?
A prime number is any integer evenly divisible by only itself, and the number 1. Since 21 is divisible by 3 and 7, it is a composite number, not a prime number.No, 21 is not a prime number.21 is divisible by 1, 3, 7, & 21No. 21=3*7
Why is the number 21 composite?
Because 21 is divisible by numbers other than 1 and 21. 21 is divisible by 1, 3, 7, 21
What is divisible by 21?
All multiples of 21, which is an infinite number.
What number is between 21 and 39 that is divisible by 2 and 5?
If its divisible by 5 AND 2 it must be divisible by 10 So you just have to pick the only number between 21 and 39 that's divisible by 10
What number is divisible by 3 and 7?
21
Explain why 21 is not a prime number?
21 has factors other than 1 and itself, so it is not a prime number. For example, it is divisible by 3. (You can check this by adding the digits of the number: 2 + 1 = 3. If the sum of the digits is divisible by 3, the number is also divisible by 3.) Therefore, 21 is a composite number.
What numbers can be divided by 3?
The divisibility rule for 3 is as follows: If the sum of the digits of a number is divisible by 3 then the number is divisible by 3. For example, the number 21 is divisible by 3 since 2+1=3, and 3 is divisible by 3. The number 49 is not divisible by 3 since 4+9=13, and 13 is not divisible by 3.
What number is divisible by 3 and not by 6?
27, 21
Which number between 190 and 200 is divisible by 9?
Is 21 a prim number?
No, it is composite. 21 is divisible by 1, 3, 7, and 21. =)
