1. The problem statement, all variables and given/known data How many times does digit 5 occur in numbers fro 0-1000. 2. Relevant equations 3. The attempt at a solution This is what i have done. Total (1,2,3) digit numbers which have digit 5 occuring once in them are-: [itex] 3.^9C_1.^9C_1 = 243 [/itex] Total numbers with 5 occuring twice are [itex] ^9C_1 = 9 [/itex] So, digit 5 occurs 9*2=18 times Total Numbes with 5 occuring thrice= 1 So digit 5 occurs 3*1=3 Total times digit 5 occurs is 243+18+1=264 Is this correct, specially regarding repetitions or exclusions which i may have made?