《2025年口算训练六年级数学上册人教版双色升级版》

$\frac {7}{20}×25= $
$\frac {4}{63}×9= $
$\frac {2}{15}×5= $
$13×\frac {7}{26}= $
$4×\frac {4}{9}= $
$20×\frac {3}{10}= $
$70×\frac {3}{7}= $
$50×\frac {7}{10}= $
$60×\frac {3}{10}= $
$\frac {3}{4}×\frac {3}{4}= $
$100×\frac {17}{25}= $
$\frac {8}{51}×17= $
$80×\frac {5}{8}= $

答案： 解析：
这些题目都是基础的分数乘法口算题，主要考察分数乘法的运算规则，即分子乘分子作为新的分子，分母乘分母作为新的分母，能约分的先约分。
答案：
$\frac {7}{20}×25= \frac{35}{4}$，
$\frac {4}{63}×9= \frac{4}{7}$，
$\frac {2}{15}×5= \frac{2}{3}$，
$13×\frac {7}{26}= \frac{7}{2}$，
$4×\frac {4}{9}= \frac{16}{9}$，
$20×\frac {3}{10}= 6$，
$70×\frac {3}{7}= 30$，
$50×\frac {7}{10}= 35$，
$60×\frac {3}{10}= 18$，
$\frac {3}{4}×\frac {3}{4}= \frac{9}{16}$，
$100×\frac {17}{25}= 68$，
$\frac {8}{51}×17= \frac{8}{3}$，
$80×\frac {5}{8}= 50$。

$\frac {5}{21}×\frac {3}{8}= $
$85×\frac {3}{5}= $
$\frac {7}{16}×80= $
$\frac {10}{7}×\frac {3}{20}= $
$\frac {6}{17}×\frac {51}{28}= $
$\frac {2}{7}×\frac {7}{8}= $
$\frac {1}{5}+\frac {1}{6}= $
$\frac {1}{3}-\frac {1}{4}= $
$\frac {23}{56}×8= $
$\frac {14}{15}×\frac {3}{7}= $
$\frac {5}{8}×\frac {7}{30}= $
$\frac {11}{36}×\frac {6}{7}= $
$42×\frac {3}{14}= $

答案： 解析：
这些题目都是基础的数学运算，包括分数的乘法和加减法。我们将逐一计算每个表达式的结果。
答案：
$\frac{5}{21} × \frac{3}{8} = \frac{5 × 3}{21 × 8} = \frac{15}{168} = \frac{5}{56}$
$85 × \frac{3}{5} = \frac{85 × 3}{5} = \frac{255}{5} = 51$
$\frac{7}{16} × 80 = \frac{7 × 80}{16} = \frac{560}{16} = 35$
$\frac{10}{7} × \frac{3}{20} = \frac{10 × 3}{7 × 20} = \frac{30}{140} = \frac{3}{14}$
$\frac{6}{17} × \frac{51}{28} = \frac{6 × 51}{17 × 28} = \frac{306}{476} = \frac{9}{14}$
$\frac{2}{7} × \frac{7}{8} = \frac{2 × 7}{7 × 8} = \frac{14}{56} = \frac{1}{4}$
$\frac{1}{5} + \frac{1}{6} = \frac{6}{30} + \frac{5}{30} = \frac{11}{30}$
$\frac{1}{3} - \frac{1}{4} = \frac{4}{12} - \frac{3}{12} = \frac{1}{12}$
$\frac{23}{56} × 8 = \frac{23 × 8}{56} = \frac{184}{56} = \frac{23}{7}$
$\frac{14}{15} × \frac{3}{7} = \frac{14 × 3}{15 × 7} = \frac{42}{105} = \frac{2}{5}$
$\frac{5}{8} × \frac{7}{30} = \frac{5 × 7}{8 × 30} = \frac{35}{240} = \frac{7}{48}$
$\frac{11}{36} × \frac{6}{7} = \frac{11 × 6}{36 × 7} = \frac{66}{252} = \frac{11}{42}$
$42 × \frac{3}{14} = \frac{42 × 3}{14} = \frac{126}{14} = 9$

$\frac {1}{3}×\frac {3}{5}×\frac {5}{6}=$$\frac{1}{6}$
$\frac {4}{7}×\frac {3}{7}×21=$$\frac{36}{7}$
$\frac {7}{8}×\frac {5}{14}×16=$5
$\frac {3}{25}×\frac {5}{6}×60=$6
$\frac {4}{75}×\frac {1}{8}×25=$$\frac{1}{6}$
$\frac {5}{9}×\frac {2}{15}×9=$$\frac{2}{3}$
$70×\frac {2}{15}×\frac {5}{7}=$$\frac{20}{3}$
$\frac {5}{18}×\frac {4}{7}×\frac {9}{5}=$$\frac{2}{7}$
$\frac {7}{15}×\frac {3}{5}×\frac {5}{14}=$$\frac{1}{10}$
$80×\frac {7}{10}×\frac {3}{14}=$12
$64×\frac {3}{4}×\frac {7}{8}=$42
$\frac {5}{6}×\frac {3}{4}×72=$45
$\frac {4}{15}×\frac {7}{18}×30=$$\frac{28}{9}$

答案： $\frac{1}{3}×\frac{3}{5}×\frac{5}{6}=\frac{1×3×5}{3×5×6}=\frac{1}{6}$
$\frac{4}{7}×\frac{3}{7}×21=\frac{4×3×21}{7×7}=\frac{4×3×3}{7}=\frac{36}{7}$
$\frac{7}{8}×\frac{5}{14}×16=\frac{7×5×16}{8×14}=\frac{5×2}{2}=5$
$\frac{3}{25}×\frac{5}{6}×60=\frac{3×5×60}{25×6}=6$
$\frac{4}{75}×\frac{1}{8}×25=\frac{4×1×25}{75×8}=\frac{1}{6}$
$\frac{5}{9}×\frac{2}{15}×9=\frac{5×2×9}{9×15}=\frac{2}{3}$
$70×\frac{2}{15}×\frac{5}{7}=\frac{70×2×5}{15×7}=\frac{10×2×1}{3}=\frac{20}{3}$
$\frac{5}{18}×\frac{4}{7}×\frac{9}{5}=\frac{5×4×9}{18×7×5}=\frac{4×1}{2×7}=\frac{2}{7}$
$\frac{7}{15}×\frac{3}{5}×\frac{5}{14}=\frac{7×3×5}{15×5×14}=\frac{1}{10}$
$80×\frac{7}{10}×\frac{3}{14}=8×7×\frac{3}{14}=8×\frac{3}{2}=12$
$64×\frac{3}{4}×\frac{7}{8}=16×3×\frac{7}{8}=2×3×7=42$
$\frac{5}{6}×\frac{3}{4}×72=\frac{5×3×72}{6×4}=5×3×3=45$
$\frac{4}{15}×\frac{7}{18}×30=\frac{4×7×30}{15×18}=\frac{4×7×2}{18}=\frac{28}{9}$