How do I find the Greatest Common Factor (GCF)? – MATH Find the greatest common factor of two whole numbers less than or equal to 100. Based on Common Core CC Standard 6.NS.B.4 12 Questions by Math_by_Kahoot 02/01/2018 answers Play What is a factor? A piece of a division problem. The small number next to a number. (ex: 5²) A number that is multiplied to get another number. An unknown number represented by a letter. How do you find the greatest common factor? Multiply each number by 5, choose the larger one. List the factors of each, find the largest one in common. Count by the numbers until you find a common number. Organize the numbers from least to greatest. What are the factors of 39? 1, 3, 13, 39 1, 39 3, 13 39, 78, 117, 156 … and 9 more awesome questions! Check them out by clicking “Play”.