6300 ÷90×c=350 HHHHHHHHHHHHHHHHHHHHHEEEEEEEEEEEEEEEEEEEEEEEEEEELLLLLLLLLLLLLLLLLLLLLLLLLLLLLL PPPPPPPPPPPPPPPPPPPPPPPPPP
6300:90*с=350 70*с=350 с=350:70 с=5
6300:90•с=350; 70•с=350; с=350:70; с=5; Ответ:5; 150•20-а=1200; 3000-а=1200; а=3000-1200; а=1800; Ответ:1800;