9.下面算式中字母都不等于0,那这些算式不正确的是( )
A. | (a+b)×c=a×c+b×c | B. | a×(b+c)=a×b+a×c | C. | (a+b)÷c=a÷c+b÷c | D. | a÷(b+c)=a÷b+a÷c |
8.下面算式中不正确的是( )
A. | (a+b)+c=a+(b+c) | B. | (a×b)×c=a×(b×c) | C. | (a+b)×c=a×b+b×c | D. | a×(b+c)=a×b+a×c |
2.用简便方法计算
0 159707 159715 159721 159725 159731 159733 159737 159743 159745 159751 159757 159761 159763 159767 159773 159775 159781 159785 159787 159791 159793 159797 159799 159801 159802 159803 159805 159806 159807 159809 159811 159815 159817 159821 159823 159827 159833 159835 159841 159845 159847 159851 159857 159863 159865 159871 159875 159877 159883 159887 159893 159901 199269
32.54-0.25+17.36-0.25 | 10.2-0.96-0.2 | 33.7-0.6-7.4-13.7 |
6.02+5.6+3.98 | 15.67-(5.67-5.49) | 6.23+3.77-2.37-0.63 |