7.口算
0 158950 158958 158964 158968 158974 158976 158980 158986 158988 158994 159000 159004 159006 159010 159016 159018 159024 159028 159030 159034 159036 159040 159042 159044 159045 159046 159048 159049 159050 159052 159054 159058 159060 159064 159066 159070 159076 159078 159084 159088 159090 159094 159100 159106 159108 159114 159118 159120 159126 159130 159136 159144 199269
120-40= | 42×5= | 25×4= | 450×0= |
360-90= | 11+60= | 630×3= | 360÷4= |
72-24= | 9+50= | 630+70= | 120×5= |