w) (500-14) x 10: [680 (635-a)] x 5 = 405
x) [136+ (42 x ax 8-905)-27x80] : 5 = 19
y) [(163 x 4+a): 100+ 182]:2+20×5=196

z) (99:9+7) x 10+ [72+ (a-2 x 44 x 3)] + 1000=1355

Va rog ajutatima repede dau coroana!