8.脱算计算.(能简算要简算.)
| $\frac{1}{3}$×[$\frac{1}{2}$÷($\frac{3}{4}$×$\frac{8}{9}$)] | $\frac{11}{7}$×$\frac{9}{20}$+$\frac{10}{7}$÷$\frac{20}{9}$ |
| 1-($\frac{5}{7}$+$\frac{3}{14}$÷$\frac{1}{4}$)×$\frac{2}{7}$ | 121÷[56×($\frac{4}{7}$-$\frac{3}{8}$)] |
| 5×( $\frac{1}{15}$+$\frac{2}{17}$ )×17 | 20.15×3099-29.99×2015 |
7.解方程或比例.
| $\frac{4}{7}$:x=0.4:14 | $\frac{3}{4}$x-25%x=21 | 4:45=$\frac{x}{27}$ |
6.直接写出下面各题的得数.
| $\frac{3}{4}$+0.25= | 1-0.04= | 1×33= | $\frac{1}{ɑ}$÷$\frac{1}{b}$= |
| 10÷10%= | 0.47+45%= | 6÷(1-$\frac{6}{7}$)= | $\frac{2}{3}$:$\frac{3}{4}$(求比值)= |
5.一个圆锥的半径扩大3倍,高不变,它的体积和底面积都扩大( )倍.
| A. | 3倍 | B. | 12倍 | C. | 9倍 |
4.男生人数与女生人数的比是5:4,男生人数比女生人数多( )
| A. | 25% | B. | 20% | C. | 80% |
3.把25g盐放入100g水中,盐水的含盐率为( )
| A. | 20% | B. | 25% | C. | 125% |
2.一个圆锥的体积是36cm3,它的底面积是18c㎡,它的高是( )cm.
| A. | 2 | B. | 18 | C. | 6 |
1.下面每组中的两个比不成比例是( )
0 154716 154724 154730 154734 154740 154742 154746 154752 154754 154760 154766 154770 154772 154776 154782 154784 154790 154794 154796 154800 154802 154806 154808 154810 154811 154812 154814 154815 154816 154818 154820 154824 154826 154830 154832 154836 154842 154844 154850 154854 154856 154860 154866 154872 154874 154880 154884 154886 154892 154896 154902 154910 199269
| A. | 1.8:3和6:10 | B. | 6:9和9:11 | C. | 8:1和$\frac{4}{5}$:$\frac{1}{10}$ | D. | 0.5:0.2和$\frac{5}{8}$:$\frac{1}{4}$ |