A 4-digit number is selected at random formed by using the digits 0, 1, 2, 3 and 4 (where repetition of digits is not allowed). What is the probability that the number selected is divisible by 3?

Sum of all digits = 0+1+2+3+4 = 10. For 4-digit subset divisible by 3, we exclude one digit such that remaining sum is divisible by 3. Excluding 1: sum = 9 ✓; Excluding 4: sum = 6 ✓. Excluding 1: digits {0,2,3,4}, valid 4-digit numbers = 3×3×2×1 = 18. Excluding 4: digits {0,1,2,3}, valid 4-digit numbers = 3×3×2×1 = 18. Total = 36. Probability = 36/96 = 3/8.