Best Answer

The divisibility rule for 42 is

- divisibility by 2, AND
- divisibility by 3, AND
- divisibility by 7.

Divisibility by 2 requires the number to be even. That means it must end in 0, 2, 4, 6 or 8.

Divisibility by 3 requires that the digital root of the number is divisible by 3. That is, the sum of the digits is divisible by 3. If the first sum is large, you can calculate the digital root of the digital root (and again, if necessary) and check that for divisibility by 3.

The divisibility rule for 7 is more difficult.

Take the last digit (units).

From the number formed by the remaining digit, subtract twice the last digit.

If the answer is divisible by 7 (including zero or negative numbers), then the original number is divisible by 7.

For large numbers, repeat the process to bring the number down to a manageable size.

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Q: What is the divisibility rule for 42?

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There is no easy rule for divisibility by 34.

By tautology. If it did not work, it would not be a divisibility rule!

why does the divisibility rule work for 4

What is the divisblity rule by 8

there is a divisibility for 24 the rule is you can divide 24 as 6 and 4 i think

Related questions

There is no easy rule for divisibility by 34.

The divisibility rules of 4 and 9 are combined to make the divisibility rule of 36.

By tautology. If it did not work, it would not be a divisibility rule!

why does the divisibility rule work for 4

the divisibility rule for 2 is: The number is even;the last digit ends with a 2,4,6,8,10, etc.The divisibility rule fir 3 is: The sum of the number is divisible by 3The divisibility rule for 4 is: The last two digits are divisible by 4The divisibility rule for 5 is: The number ends with a 5 or 0The divisibility rule for 6 is: The sum CAN be divisible by 2 and or 3The divisibility rule for 9 is: The sum of the number is divisible by 9The divisibility rule for 10 is : The number ends with a 0

What is the divisblity rule by 8

The divisibility rule for 2 works because the base of our number system, 10, is divisible by 2.

there is a divisibility for 24 the rule is you can divide 24 as 6 and 4 i think

Able to Be Divided

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2.50

Judging by some of the questions asked on this site, the first rule is that divisibility is a concept that applies only to whole numbers.