0:00:01.133,0:00:05.067 We have to rewrite the following fractions 0:00:05.067,0:00:09.733 with fraction with least common denominator 0:00:09.733,0:00:16.200 So LCD of the 2 fractions is going to be the LCM 0:00:16.200,0:00:21.133 of both of these denominators over here. 0:00:21.133,0:00:25.467 and if we can make this as common denominators 0:00:25.467,0:00:29.133 we can add the two fractions 0:00:29.133,0:00:31.800 First let us find the LCM, 0:00:31.800,0:00:49.200 let me write it out LCD of 8 & 6 0:00:49.200,0:00:58.133 is going to be the LCM of 8 & 6 0:00:58.133,0:01:00.800 and a couple of ways to think about the LCM 0:01:00.800,0:01:03.267 you could really take the multiples of 8 & 6 0:01:03.267,0:01:08.600 and see what their smallest common multiple is. 0:01:08.600,0:01:20.867 Multiples of 6 - 6,12,18,24,30... i can keep going 0:01:20.867,0:01:27.267 and the multiples of 8 are 8,16,24,. looks like 0:01:27.267,0:01:32.733 we are done. I have found a common multiple 0:01:32.733,0:01:35.467 it is the smallest multiple they have other 0:01:35.467,0:01:39.867 common multiples like 48,72 and we can go on 0:01:39.867,0:01:43.400 but this is their smallest common multiple 0:01:43.400,0:01:50.933 So it is 24. Another way to find the LCM is 0:01:50.933,0:01:55.800 take the prime factorization of 6 - 2x3 0:01:55.800,0:02:02.600 and the LCM of 6 must have one 2 & one 3 0:02:02.600,0:02:13.667 what is the prime factorization of 8 is 2x2x2. 0:02:13.667,0:02:16.467 Inorder to be divisible by 8 we need to have three 2's 0:02:16.467,0:02:19.133 in the prime factorization. To be divisible by 6 0:02:19.133,0:02:23.800 we need to have 2,3 and to be divisible by 8 we need 0:02:23.800,0:02:28.867 three 2's, we have only one 2 so we add a couple more 0:02:28.867,0:02:42.133 so thsi is now divisible by 6 & 8 0:02:42.133,0:02:49.733 So 2x2x2x3 = 24. So LCM of 8 & 6 0:02:49.733,0:02:54.200 which is the LCD also is 24 0:02:54.200,0:02:58.200 So we want to write each of this fractions as 0:02:58.200,0:03:01.600 24 as their denominator. 0:03:01.600,0:03:09.733 So lets start with 2/8, i want to write that as / 24 0:03:09.733,0:03:13.400 so get the denominator as 24, 0:03:13.400,0:03:17.533 we need to multiply the denominator by 3 0:03:17.533,0:03:19.400 inorder not to change the fraction, we need to 0:03:19.400,0:03:24.067 multiply the numerator also by the same number 0:03:24.067,0:03:28.600 so we will multiply numerator by 3 ; 2x3=6 0:03:28.600,0:03:33.400 so 2/8 = 6/24 0:03:33.400,0:03:43.267 2/8 x 3/3 = 6/24 0:03:46.867,0:03:59.800 and lets do the same things with 5/6 0:03:59.800,0:04:09.533 5/6 = / 24, i will do it in a different colour, blue 0:04:09.533,0:04:13.067 to get the denominator from 6 to 24, we need 0:04:13.067,0:04:17.667 to multiply by 4, so we need to multiply 0:04:17.667,0:04:24.800 numerator also by 4 so 5x4 = 20 0:04:24.800,0:04:28.133 5/6 = 20/24 0:04:28.133,0:04:33.400 so we have written both the fractions with common denominator 0:04:33.400,9:59:59.000 So we are done