What Are Factors Of 16:
1)2, 4, 8
2)4, 16
3)1, 2, 4
4)2, 4, 8
What are the factors of 18?
– 1.2 3 6 9 18
What are the factors of 15?
– 1 5
What are the factors of 25?
– 1 5 10 25 100 1000 etc., a pattern which is followed in finding the number of factors is that it will be twice the last digit. For example, for 100, you have two zeros, and hence it follows a pattern which is ‘n squared.’ So if you want to find the number of factors, multiply the last digit by itself. The number formed by adding these squared numbers is the total number of factors.
So in the case of 25, 1+5+10+25=41, and 41 is the total number of factors for 25. Similarly, 100 has ten squared numbers (1+4+9+16+25+36+49+64+81), which sum up to 100.
Some other perfect squares are: 4, 9, 16, 25, 36, 49, 64, 81. Notice that these are all multiples of 2 and 5. This is not a coincidence! The factors of a perfect square always include 1, 2, 4, and the square itself.
What about numbers that are not perfect squares? For example, the number 15. 15 is not a perfect square, so it has different factors. The prime factors of 15 are 3 and 5. 1, 3, 5, 15 are all elements of 15.
One other thing to note is that the sum of all the number factors (except for the number itself) is always divisible by the number’s most significant common factor (GCF). For example, the GCF of 15 and 25 is 5. So the sum of all the 15 and 25 (1+3+5+15+25) is 60, divisible by 5.
The most significant common factor (GCF) is the largest number divided evenly into two numbers. To find the GCF of two numbers, you first see the prime factorization of each number. The GCF is simply the product of all those prime factors in both numbers.
For example, what are the GCF and individual factors for 18? – 1.2 3 6 9 18
The list below shows that these three numbers have a GCF of 2:
1.Prime Factorization: 2 x 2 x 3 = 8
2.Greatest Common Factor (GCF): 2 x 3 = 6
3.Individual Factors: 1, 2, 3, 6
The individual factors of 18 are 1, 2, 3, and 6.
The GCF of 15 and 25 is 5.
The prime factorizations of 15 and 25 are:
1.Prime Factorization: 3 x 5 = 15
2.Greatest Common Factor (GCF): 3 x 5 = 15
3.Individual Factors: 1, 3, 5, 15
So the individual factors of 15 and 25 are 1, 3, 5, and 15. The GCF is the same for both numbers.
Lastly, let’s take a look at the number 8.
What are its factors?
– 1 2 4 8
The individual factors of 8 are 1, 2, 4, and 8. There is no GCF for these numbers.
In general, the individual factors of a number are all the numbers that can be divided evenly into the number. WHEN YOU SEPARATE THESE TWO NUMBERS, the GCF is the most significant number in both the numerator and denominator. It’s always good to find the GCF first before seeing the individual factors. This will make it much easier!
Factors Of 16 Factors Of 18 1, 2, 4, 8 1, 2, 3, 6, 9, 18
So as you can see, there are many different ways of finding out the factors of a number. The easiest way is to use a chart like the one above and cross off numbers as you go. This will help you see which numbers are factors and which ones are not. Another method is to use prime factorization to find all prime numbers that make up a specific number. Lastly, you can also use the most significant common factor (GCF) to see all the two or more numbers elements.
Whichever method you choose, it’s important to remember that the factors of a number always include 1, 2, 4, and the number itself. And finally, the sum of all the elements of a number (except for the number itself) is always divisible by its most significant common factor.