Finding of common multiples and common factors (LCM and HCF)
LCM: Lowest Common Multiple. HCF: Highest Common Factor. Examples on HCF: 1. Find the HCF of 6 and 16 Factors of 6 = {1, 2, 3, 6} Factors of 16 = {1, 2, 4, 8, 16} Common factors = {1, 2} The greatest is 2 so HCF of 6 and 16 is 2 2. Find the HCF of 24 and 54 Factors of 24 = {1, 2, 3, 4, 6, 8, 12, 24} Factors of 54 = {1, 2, 3, 6, 9, 18,27,54} Common factors = {1, 2, 3, 6} The greatest is 6 so HCF of 24 and 54 is 6 Exercises on HCF 1. Find the HCF between the following; a. 2 and 6 b. 12 and 36 c. 54 and 62 Bonus: 72 and 108 Examples on LCM 1. Find the LCM of 4 and 6 Multiples of 4 = {4, 8, 12, 16, 20, 24, ...} Multiples of 6 = {6, 12, 18, 24, 30, 36, ...} We might have too many multiples, but we need the lowest. A few of them are {12, 24, ...} The lowest multiple is 12 . 2. Find the LCM of 5 and 7 Multiples of 5 = {5, 10, 15, 20, 25, 30, 35, ...} Multiples of 7 = {7, 14, 21, 28, 35, ...} The multiples are still numerous but we need the lowest. ...