3 dice can fall in exactly 63 or 216 ways. 3 dice can have sum 3 in exactly 1 way. 3 dice can have sum 4 in exactly 3 ways. 3 dice can have sum 5 in exactly 6 ways. 3 dice can have sum 6 in exactly 10 ways. 3 dice can have sum 7 in exactly 15 ways. 3 dice can have sum 8 in exactly 21 ways. 3 dice can have sum 9 in exactly 25 ways. 3 dice can have sum 10 in exactly 27 ways. 3 dice can have sum 11 in exactly 27 ways. 3 dice can have sum 12 in exactly 25 ways. 3 dice can have sum 13 in exactly 21 ways. 3 dice can have sum 14 in exactly 15 ways. 3 dice can have sum 15 in exactly 10 ways. 3 dice can have sum 16 in exactly 6 ways. 3 dice can have sum 17 in exactly 3 ways. 3 dice can have sum 18 in exactly 1 way. Note that 1+3+6+10+15+21+25+27+27+25+21+15+10+5+3+1 = 216 = 63. So there are 216×216 or 46656 ways both sets of dice can fall. That will be the denominator of the desired probability. The number of ways both sets of dice can have sum 3 is 1×1 or 1. The number of ways both sets of dice can have sum 4 is 3×3 or 9. The number of ways both sets of dice can have sum 5 is 6×6 or 36. The number of ways both sets of dice can have sum 6 is 10×10 or 100. The number of ways both sets of dice can have sum 7 is 15×15 or 225. The number of ways both sets of dice can have sum 8 is 21×21 or 441. The number of ways both sets of dice can have sum 9 is 25×25 or 625. The number of ways both sets of dice can have sum 10 is 27×27 or 729. The number of ways both sets of dice can have sum 11 is 27×27 or 729. The number of ways both sets of dice can have sum 12 is 25×25 or 625. The number of ways both sets of dice can have sum 13 is 21×21 or 441. The number of ways both sets of dice can have sum 14 is 15×15 or 225. The number of ways both sets of dice can have sum 15 is 10×10 or 100. The number of ways both sets of dice can have sum 16 is 6×6 or 36. The number of ways both sets of dice can have sum 17 is 3×3 or 9. The number of ways both sets of dice can have sum 18 is 1×1 or 1. 1+9+36+100+225+441+625+729+729+625+441+225+100+36+9+1 = 4332 Therefore the desired probability is= or about 0.0928497942 Edwin