procedure to find the factors of 30: when you want to start calculating the factors start from 1. 1 is a common factor for all numbers. the following table shows the factors of 30 1 X 30 = 30 2 X 15 = 30 3 X 10 = 30 5 X 6 = 30 6 X 5 = 30 10 X 3 = 30 15 X 2 = 30 30 X 1 = 30 as shown in the above table in first row multiply 1 by number 30. from second row try for all possible numbers so that their multiplication gives 30. then the first column shows the factors of number 30 which are shown in red colour: factors of number 30: 1,2, 3, 5, 6,10,15, 30. if you divide the 30 with any one of the above factors reminder is zero