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Our online tests allow your kids to test their math skills. We make sure that your kids are having fun while studying by combining testing and practice sessions with cleverly designed math games.
Math is Fun
This site is an online mathematics and science school
where you can study without leaving your home (online education).
"Do not worry about your difficulties in mathematics, I assure you that mine are greater". Einstein, Albert (1879-1955)
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Divisibility criteria
Divisibility by 2. A number is divisible by 2, if its last digit is 0 or is divisible by 2. Numbers, which are divisible by 2 are called even numbers. Otherwise, numbers are called odd numbers.

Divisibility by 4. A number is divisible by 4, if its two last digits are zeros or they make a two-digit number, which is divisible by 4.

Divisibility by 8. A number is divisible by 8, if its three last digits are zeros or they make a three-digit number, which is divisible by 8.

Divisibility by 3 and by 9. A number is divisible by 3, if a sum of its digits is divisible by 3. A number is divisible by 9, if a sum of its digits is divisible by 9.

Divisibility by 6. A number is divisible by 6, if it is divisible by 2 and by 3.

Divisibility by 5.v A number is divisible by 5, if its last digit is 0 or 5.

Divisibility by 25. A number is divisible by 25, if its two last digits are zeros or they make a number,
which is divisible by 25.

Divisibility by 10. A number is divisible by 10, if its last digit is 0.

Divisibility by 100. A number is divisible by 100, if its two last digits are zeros.

Divisibility by 1000. A number is divisible by 1000, if its three last digits are zeros.

Divisibility by 11. A number is divisible by 11 if and only if a sum of its digits, located on even places is equal to a sum of its digits, located on odd places, OR these sums are differed by a number, which is divisible by 11.

There are criteria of divisibility for some other numbers, but these criteria are more difficult and not considered in a secondary school program.
Example:
A number 378015 is divisible by 3, because a sum of its digits 3 + 7 + 8 + 0 + 1 + 5 = 24, which is divisible by 3. This number is divisible by 5, because its last digit is 5. At last, this number is divisible by 11, because a sum of even digits: 7 + 0 + 5 =12 and a sum of odd digits: 3 + 8 + 1 = 12 are equal. But this number isn’t divisible by 2, 4, 6, 8, 9, 10, 25, 100 and 1000, because … Check these cases yourself !

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Math Plus Fun