三年级口算题:一位数除整十整百数 (1)640 ÷ 8 = (2)840 ÷ 6 = (3)120 ÷ 3 = (4)540 ÷ 9 = (5)400 ÷ 8 = (6)900 ÷ 9 = (7)480 ÷ 8 = (8)300 ÷ 6 = (9)400 ÷ 4 = (10)420 ÷ 3 = (11)400 ÷ 8 = (12)400 ÷ 4 = (13)880 ÷ 4 = (14)650 ÷ 5 = (15)270 ÷ 3 =