Three
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.
Those for 1, 2, 4, 5 and 8.
12
Divisibility rules have been developed and refined by mathematicians over the centuries. It is difficult to attribute the invention of divisibility rules to a specific individual. However, some early rules can be traced back to ancient civilizations like the Egyptians, Babylonians, and Greeks. These rules were further expanded upon and formalized by various mathematicians throughout history.
Three
It is: 7
Factors are divisors. If you know the divisibility rules, you know that 80 is divisible by 1, 2, 4, 5 and 8. If you divide 80 by those numbers, you find the other half of the factor pairs.
Divisibility rules help you find the factors of a number. Once you've found the factors for two or more numbers, you can find what they have in common. Take 231 and 321. If you know the divisibility rules, you know that they are both divisible by 3, so 3 is a common factor.
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.
Those for 1, 2, 4, 5 and 8.
The divisibility rules for a prime number is if it is ONLY divisible by 1, and itself.
By using the divisibility rules, I can tell that 864 is divisible by 2, 3, 4, 6, 8 and 9. By dividing those numbers into 864 I can create factor pairs, any of which I can use to start the tree. 864 432,2 216,2,2 108,2,2,2 54,2,2,2,2 27,2,2,2,2,2 9,3,2,2,2,2,2 3,3,3,2,2,2,2,2
12
You can always check on the divisibility of a number by dividing it into another number. But if you know the divisibility rules, you can get that information easier and faster.
i think divisibility rules help with fractions because it helps you reduce the fraction to make i a simple fraction.
3 and 9. And they divide into 123456789 whether or not you use divisibility rules!