The idea of the solution is vary simple. First, we should calculate the number of all possible groups of 6 numbers, selected from 48 numbers. This number is= = 12271512. Next we should calculate the number of all possible groups ot 6 numbers, that contain 4 particular numbers. This numbers is = = 946 (since we can combine any of 2 remained 48-4 = 44 numbers with 4 particular numbers). Finally, the desired probability is the ratio P = = . ANSWER