{ [ ( 8 + a - 98 ) : 2 - 56 ] x 6 - 268 } : 2 = 55
[ ( 8 + a - 98 ) : 2 - 56 ] x 6 - 268 = 55 × 2
[ ( 8 + a - 98 ) : 2 - 56 ] x 6 - 268 = 110
[ ( 8 + a - 98 ) : 2 - 56 ] x 6 = 110 + 268
[ ( 8 + a - 98 ) : 2 - 56 ] x 6 = 378
( 8 + a - 98 ) : 2 - 56 = 378 : 6
( 8 + a - 98 ) : 2 - 56 = 63
( 8 + a - 98 ) : 2 = 63 + 56
( 8 + a - 98 ) : 2 = 119
8 + a - 98 = 119 × 2
8 + a - 98 = 238
8 + a = 238 + 98
8 + a = 336
a = 336 - 8
a = 328 → numarul, aflat prin metoda mersului invers