On the first week of math 10 we learned how to find GCF.
GCF is the greatest common factor of numbers.
To find a GCF you need to find prime factors of each number by using a factor tree.
For example we have 483 and 575 and we need to find GCF of these numbers.
Prime factors of 483 are 3, 7 and 23.
Prime factors of 575 are 5, 5 and 23.
Next step to find a greatest common factor is to check do these numbers have the same prime factors.
In our example we can see that 483 and 575 have 23 in common, and because it is the only number in common it will be the answer.
GCF=23
In second example we need to find GCF of 1700 and 1938.
Prime factors of 1700 are 2, 2, 5, 5, 17.
Prime factors of 1938 are 2, 3, 17, 19.
Now we need to find the same prime factors in both numbers.
We can see that 2 and 17 are the same in both numbers.
We need to multiply them in order to get a final answer.
By multiplying we get that GCF=34.
