1) 7,8×2,7/9×0,3×3,9 = 21,06/10,8 = 195/100 = 39/202) 8a×16a/2×8a = 128a^2/16a = 8a3) 31×90-35×31/35×31 = 2790-1085/1085 = 1705/1085 = 341/2174) 57x+19x/19x×4 = 76x/76x = 1
1) 7,8×2,7/9×0,3×3,9 = 21,06/10,8 = 195/100 = 39/20
2) 8a×16a/2×8a = 128a^2/16a = 8a
3) 31×90-35×31/35×31 = 2790-1085/1085 = 1705/1085 = 341/217
4) 57x+19x/19x×4 = 76x/76x = 1