The answers are 8,12,16,20....solution: The equations would be 1st multiple = (4*x)……2nd multiple = [4*(x+1)]…3rd multiple = [4*(x+2)]…...4th multiple = [4*(x+3)]" . To find x, you will use the given condition in the question, it says 1st multiple plus 2nd multiple is equal to the 4 the multiple. Therefore, the equation would be, "(4*x) + [4*(x+1)] = [4*(x+3)]". The answer would be x=2. Then substitute it to x in the 4 equations to get the multiples.