Presentation on theme: "Prepare for Cornell notes. GFC is simply …. the greatest number that is a factor of two or more numbers …. is called Greatest Common Factor. Greatest."— Presentation transcript:
Prepare for Cornell notes
GFC is simply …. the greatest number that is a factor of two or more numbers …. is called Greatest Common Factor. Greatest number = the highest possible number Factor = a number that makes up a product Example: 3 x 2 = 6 3,2 are the factors and 6 is the product Factor….. Think of facts Facts make up a story. Facts are all the smaller details that together make the whole story so…..
Just as facts make the story Factors should always be smaller than the numbers you are comparing…or at least same as one of the numbers. Example: Find the GCF of 6 and 12 6 is a factor of 12 ….2x6 =12 6 is a factor of 6 …..1x6= 6
The are 2 basic methods to finding GCF Depending on your style you may prefer one over the other. However, you will learn both and will be able to successfully use both as you will be asked on various tests to prove that you can solve using a particular method. The methods are referred to as 1. Listing Method 2.Prime factorization aka “factor trees”
Find the GCF of 12 and 20 1) List the factors of each. Factors of 12: 1,2,3,4,6,12 Factors of 20: 1,2, 4,5,10,20 2) Pick out the common factors 3) Select the Greatest. Easy- Squeezie!!
Prime Factor …. Prime factorization…. Number that can not be factored any lower/smaller than 1, and itself …. Like 2, 3, 5, 7, Not 6… 2x3 or 8…2x4 is finding the factors of a number that are all prime.prime.
Easy to remember …THEY LOOK LIKE TREES!! Christmas to be exact.
Here's an example: Find the prime factors of the number 84:Find the prime factors of the number 84: on you white board….hold it up when you done. Here's how you do it: Find 2 factors of your number. Then look at your 2 factors and determine if one or both of them is not prime. If it is not a prime factor it. Repeat this process until all your factors are prime. 84 / \ 42 x 2 (84 is 42 times 2) / \ 21 x 2 (42 is 21 times 2) / \ 7 x 3 (21 is 7 times 3) (7 and 3 are both prime, so we stop!)
1) Create a factor tree for both numbers. 2) Circle the Common Prime the end) 3) Multiply the common prime factors. 4) The product (answer) is your GCF!!