[tex]{(328 + 41 - a) \div 6} \times 3 + 157 = 337[/tex]
Se aplică metoda mersului invers.
[tex](328 + 41 - a) \div 6 \times 3 = 337 - 157 \\ (328 + 41 - a) \div 6 \times 3 = 180 \\ (328 + 41 - a) \div 6 = 180 \div 3 \\ (328 + 41 - a) \div 6 = 60 \\ 328 + 41 - a = 360 \\ 369 - a = 360 \\ a = 369 - 360 \\ a = 9[/tex]
