1)340*х-316*2=18,208
2) (31*550-х)*120=10,200

340*x=18,208+632,340*x=650,208,x=650,208:340,x=1,912.2) (31*550-х)*120=10,200,31*550-x=10,200:120,31*550-x=0,085,17050-x=0,085,x=17050-0,085=17049,915.