metoda mersului invers

[tex]m \div 2 + 45 - 25 \div (36 - 99 \div 9) = [/tex]
[tex](a \div 5 + 105) \div 100 = [/tex]
[tex]3 \times (420 - 6 \times p) \div 64 = [/tex]
[1256:10-(46+14×b)]×3=
[(827-4×200-2×1)×6-123]÷a=​