Номер 871

(800 – 600) · 4 = 800;
(120 – 60) · 4 = 240;
(48 – 30) · 4 = 72;
(600 + 200) : 4 = 200;
(80 + 80) : 4 = 40;
(240 + 120) : 4 = 90.