20.口算.
63+26= | 94-38= | 53-17= | 360+450= |
330-180= | 457+385= | 400-150= | 248+96= |
19.要使●是○的2倍,再画( )个●.
A. | 3 | B. | 4 | C. | 5 | D. | 2 |
14.直接写结果.
1.5×4= | 0.12×3= | 0.49÷0.7= | 42÷0.6= |
72.8÷0.8= | 1.5÷30= | 0.6×1.5= | 0÷19.7= |
6.4×0.2+3.6×0.2= | 3×0.2×0.5= |
13.6.8×101=6.8×100+6.8×1是运用了( )
0 163607 163615 163621 163625 163631 163633 163637 163643 163645 163651 163657 163661 163663 163667 163673 163675 163681 163685 163687 163691 163693 163697 163699 163701 163702 163703 163705 163706 163707 163709 163711 163715 163717 163721 163723 163727 163733 163735 163741 163745 163747 163751 163757 163763 163765 163771 163775 163777 163783 163787 163793 163801 199269
A. | 乘法交换律 | B. | 乘法结合律 | C. | 乘法分配律 |