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If a number is divisible by anything other than itself and 1, it's composite.

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Q: How can your knowledge of divisibility rules help you to determine whether a number is prime or composite?

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A number can be factored to determine whether it is prime or composite. A prime number has exactly 2 factors, 1 and the number itself. A composite number has more than two factors.

You use divisibility rules t determine whether a particular number is (or is not) a factor of another number. If it is a factor, you can reduce the numbers involved to smaller numbers.You might want to find factors to simplify fractions or to add or subtract factions.

That depends what you need to "solve". If what you want to do is check whether a number is prime or composite, check whether it is divisible by 2, and then by all odd numbers up to the square root of your number. For example, for numbers up to 120, you only need to check whether they are divisible by 2, 3, 5, 7 (9 is composite, so you don't really need to check divisibility by 9). If your number is divisible by any such number, then it is composite; otherwise it is a prime. There are more efficient methods, but they are also more complicated, and it really only makes sense to use them for much larger numbers.

To keep it simple: Write a main loop that goes through all the numbers, starting with 2, and incrementing one at a time. Determine whether each number is a prime number. If it is, increment a counter. To determine whether each number is a prime number, either use an inner loop, or a separate function. Test divisibility of the number "n" by every number from 2 to n-1. If you find a factor, then it is not a prime number. Note that you can test divisibility by using the "%" operator. For example: if (number % factor == 0) // number is divisible by factor else // it isn't

Now.... That depends on whether it is a number orr not!? :)

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It's composite

evaluating test results.

I suggest you try dividing it by different numbers, and see whether it is divisible. If you find a divisor, then it is composite. Otherwise it is a prime. For numbers up to 120, it is sufficient to test divisibility by 2, 3, 5, and 7.

If it has more than two factors.

A number can be factored to determine whether it is prime or composite. A prime number has exactly 2 factors, 1 and the number itself. A composite number has more than two factors.

By trying out whether you can divide it by different numbers. For one- or two-digit numbers, it is enough to test divisibility by 2, 3, 5, 7.

to determine whether an employee has the required knowledge and that an employee can work effectively

You use divisibility rules t determine whether a particular number is (or is not) a factor of another number. If it is a factor, you can reduce the numbers involved to smaller numbers.You might want to find factors to simplify fractions or to add or subtract factions.

Not sure what you meant, but 242 is not divisible by 3. By adding all digits, you can determine whether it is a multiple of 3 or not.

3 and 9. And they divide into 123456789 whether or not you use divisibility rules!

I don’t

Use the divisibility rule for 10. If the number is divisible by 10, then it is obviously also divisible by 5.

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