小学四年级下册口算题练习64080= 155= 233= 1225= 48080= 165= 273= 9015= 484= 64016= 393= 2420= 323= 4816= 128= 273= 5614= 248= 142= 83-45= 56080= 9624= 4020= 4030= 37+26= 76-39= 605+59= 3023= 128= 27+32= 48+27= 450020= 73+15 = 120600 = 200360= 6800400= 280+270= 42500= 600040= 51280= 310-70= 40014= 470+180= 100025= 160600= 20420= 290300= 8100300= 7600200= 7600400= 680+270= 98014= 420030= 61300= 130050= 20048= 930-660= 530+280= 9200400= 84021= 180500= 8000500 = 190020= 200160= 8700300= 300330= 31400= 700014= 60012= 960080= 140300= 880040= 9600800= 750-290= 5490= 76020= 7500500= 370200= 65013= 8600-4200= 2404=