12．直接写得数
| 8.9-4.1= | 3-0.15= | 61+98= | 2.9+2.7= |
| 9.3-0.2= | 2.5×4= | 96÷4= | 68×50= |
| 0.02×0.5= | 0.7×1.9= |
8．列各分数约分．
| $\frac{36}{54}$ | $\frac{28}{35}$ | $\frac{48}{144}$ | $\frac{54}{72}$ |
3．用2、3、4三个数字组成一个既有因数2，又是3的倍数的三位数，能组成（ ）个这样的三位数．
0 137877 137885 137891 137895 137901 137903 137907 137913 137915 137921 137927 137931 137933 137937 137943 137945 137951 137955 137957 137961 137963 137967 137969 137971 137972 137973 137975 137976 137977 137979 137981 137985 137987 137991 137993 137997 138003 138005 138011 138015 138017 138021 138027 138033 138035 138041 138045 138047 138053 138057 138063 138071 199269
| A． | 2个 | B． | 4个 | C． | 6个 | D． | 0个 |