《2025年阳光同学暑假口算五升六数学》

1. 直接写出得数。
$\frac {2}{5}+\frac {1}{5}= $ $\frac {3}{8}-\frac {1}{8}= $ $\frac {1}{2}+\frac {1}{2}= $ $1-\frac {7}{9}-\frac {1}{9}= $
$\frac {8}{9}-\frac {8}{9}= $ $\frac {7}{20}+\frac {11}{20}= $ $\frac {3}{7}+\frac {5}{7}= $ $\frac {3}{5}+\frac {4}{5}-\frac {2}{5}= $
$\frac {3}{17}+\frac {4}{17}= $ $\frac {5}{11}-\frac {2}{11}= $ $\frac {9}{20}-\frac {7}{20}= $ $\frac {2}{7}+\frac {5}{7}-1= $
$\frac {7}{9}-\frac {2}{9}= $ $\frac {3}{8}+\frac {3}{8}= $ $\frac {6}{13}+\frac {1}{13}= $ $\frac {7}{12}+\frac {5}{12}+\frac {1}{12}= $
$1+\frac {5}{8}= $ $\frac {18}{19}-\frac {7}{19}= $ $\frac {17}{32}-\frac {15}{32}= $ $1-\frac {3}{10}-\frac {2}{10}= $
$\frac {13}{15}-\frac {4}{15}= $ $\frac {8}{27}+\frac {7}{27}= $ $\frac {25}{28}-\frac {13}{28}= $ $\frac {2}{3}+\frac {1}{3}+\frac {5}{3}= $

答案： 1. $\frac{3}{5}$，$\frac{1}{4}$，1，$\frac{1}{9}$，0，$\frac{9}{10}$，$\frac{8}{7}$，1，$\frac{7}{17}$，$\frac{3}{11}$，$\frac{1}{10}$，0，$\frac{5}{9}$，$\frac{3}{4}$，$\frac{7}{13}$，$1\frac{1}{12}$，$1\frac{5}{8}$，$\frac{11}{19}$，$\frac{1}{16}$，$\frac{1}{2}$，$\frac{3}{5}$，$\frac{5}{9}$，$\frac{3}{7}$，$2\frac{2}{3}$

2. 计算下面各题,怎样简便就怎样算。
$\frac {9}{11}+\frac {6}{11}-\frac {4}{11}$ $\frac {3}{14}+\frac {2}{5}+\frac {11}{14}+\frac {3}{5}$ $\frac {5}{6}-\frac {4}{9}+\frac {1}{6}-\frac {5}{9}$

答案： 2. 1，2，0

3. 解方程。
19x-8x=55       0.8(x+2.15)=40        0.8x+16.8=33.6

答案： x=5   x=47.85    x=21