The number of 4-digit numbers possible using 1,1,2, and 4 is 2!4!​=12 Number of 1’s, 2’s and 4’s in units digits will be in the ratio 2:1:1, i.e. 61 ’s, 3 2’s and 34 ’s.Sum=6(1)+3(2)+3(4)=24 Similarly, in tens digit, hundreds digit and thousands digit as well. Therefore, sum =24+24(10)+24(100)+24(1000)=24(1111) Mean =1224(1111)​=2222 The answer is option A.