《2025年练习与测试六年级数学上册苏教版培优版》

1. 直接写出得数。(8分)
$\dfrac{1}{5}÷ \dfrac{2}{3}=$$\dfrac{3}{10}$ $1÷ \dfrac{2}{5}=$$\dfrac{5}{2}$ $\dfrac{3}{4}+\dfrac{1}{3}=$$\dfrac{13}{12}$ $\dfrac{1}{8}× 5=$$\dfrac{5}{8}$
$\dfrac{5}{7}× \dfrac{2}{5}=$$\dfrac{2}{7}$ $\dfrac{2}{3}-\dfrac{1}{5}=$$\dfrac{7}{15}$ $\dfrac{2}{3}÷ \dfrac{3}{5}=$$\dfrac{10}{9}$ $\dfrac{7}{20}÷ \dfrac{4}{15}=$$\dfrac{21}{16}$

答案： $\dfrac{3}{10}$；$\dfrac{5}{2}$；$\dfrac{13}{12}$；$\dfrac{5}{8}$；$\dfrac{2}{7}$；$\dfrac{7}{15}$；$\dfrac{10}{9}$；$\dfrac{21}{16}$

2. 解方程。(9分)
$x-\dfrac{1}{4}x= \dfrac{7}{8}$ $1+\dfrac{1}{5}x= \dfrac{9}{5}$ $x÷ \dfrac{3}{4}× \dfrac{1}{3}= 4$

答案：
1. $ x = \dfrac{7}{6} $
2. $ x = 4 $
3. $ x = 9 $

3. 计算下面各题,能简算的要简算。(18分)
$\dfrac{5}{7}+\dfrac{4}{9}+\dfrac{2}{7}+\dfrac{5}{9}$ $\dfrac{2}{3}+\dfrac{1}{5}× \dfrac{2}{3}$ $\dfrac{4}{7}× \dfrac{3}{8}+\dfrac{3}{8}× \dfrac{3}{7}$
$30× (\dfrac{2}{5}+\dfrac{1}{6})$ $\dfrac{1}{5}÷ (\dfrac{7}{5}-\dfrac{2}{7}× \dfrac{21}{5})$ $[1-(\dfrac{1}{4}+\dfrac{1}{8})]÷ \dfrac{4}{5}$

答案： 1.
$\frac{5}{7}+\frac{4}{9}+\frac{2}{7}+\frac{5}{9}$
$=(\frac{5}{7}+\frac{2}{7})+(\frac{4}{9}+\frac{5}{9})$
$=1 + 1$
$=2$
2.
$\frac{2}{3}+\frac{1}{5}×\frac{2}{3}$
$=\frac{2}{3}×(1 + \frac{1}{5})$
$=\frac{2}{3}×\frac{6}{5}$
$=\frac{4}{5}$
3.
$\frac{4}{7}×\frac{3}{8}+\frac{3}{8}×\frac{3}{7}$
$=\frac{3}{8}×(\frac{4}{7}+\frac{3}{7})$
$=\frac{3}{8}×1$
$=\frac{3}{8}$
4.
$30×(\frac{2}{5}+\frac{1}{6})$
$=30×\frac{2}{5}+30×\frac{1}{6}$
$=12 + 5$
$=17$
5.
$\frac{1}{5}÷(\frac{7}{5}-\frac{2}{7}×\frac{21}{5})$
$=\frac{1}{5}÷(\frac{7}{5}-\frac{6}{5})$
$=\frac{1}{5}÷\frac{1}{5}$
$=1$
6.
$[1-(\frac{1}{4}+\frac{1}{8})]÷\frac{4}{5}$
$=[1-\frac{3}{8}]÷\frac{4}{5}$
$=\frac{5}{8}÷\frac{4}{5}$
$=\frac{25}{32}$