[tex] {5}^{125} \div ( {5}^{45} \times {5}^{75}) + 5 \times (363 - 3 \times 121) = \\ \\ {5}^{125} \div {5}^{120} + 5 \times (363 - 363) = \\ \\ {5}^{5} + 5 \times 0 = \\ \\ {5}^{5} + 1 = 3125 + 1 = 3126[/tex]
[tex]xxx + xx + x = 984 \\ \\ (100x + 10x + x) + (10x + x) + x = 984 \\ \\ 123x = 984 \\ \\ x = 984 \div 123 \\ \\ x = 8[/tex]
[tex]5x1 + 51x+ x51 = 1173 \\ \\ (5 \times 100 + 10x + 1) + (5 \times 100 + 1 \times 10 + x) + (100x + 5 \times 10 + 1) = 1173 \\ \\ 1062 + 111x = 1173 \\ \\ 111x = 1173 - 1062 \\ \\ 111x = 111 \\ \\ x = 111 \div 111 \\ x = 1[/tex]
