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第40页

信息发布者：

4700

9.008

$\frac {3}{28}$

$\frac {1}{32}$

12a²

7.7

$1\frac 56$

$\frac {9}{25}$

$=7×\frac {25}{14}$

$=\frac {25}{2}$

=250+168

=418

$=\frac {11}{16}+\frac {8}{13}-\frac {11}{16}-\frac {5}{13}$

$=\frac {3}{13}$

$=\frac {1}{2}-\frac {1}{4}+\frac {1}{4}-\frac {1}{8}+\frac {1}{8}-\frac {1}{16}+$

$\frac {1}{16}-\frac {1}{32}+\frac {1}{32}-\frac {1}{64}$

$=\frac {1}{2}-\frac {1}{64}$

$=\frac {31}{64}$

$\begin{aligned}解：\frac {1}{4}x&=\frac {7}{10}\\x&=\frac {14}{5}\end{aligned}$

$\begin{aligned}解：\frac {1}{3}x&=5×0.4\\\frac {1}{3}x&=2\\x&=6\end{aligned}$

$\begin{aligned}解：0.2x&=\frac {7}{5}-\frac {2}{5}\\0.2x&=1\\x&=5\end{aligned}$