二年级口算题:尾数是0三位数减法 (1)250 - 170 = (2)870 - 480 = (3)890 - 470 = (4)530 - 260 = (5)380 - 130 = (6)600 - 380 = (7)840 - 730 = (8)720 - 360 = (9)780 - 710 = (10)480 - 260 = (11)550 - 390 = (12)680 - 520 = (13)340 - 270 = (14)820 - 660 = (15)230 - 230 =