《2025年口算训练六年级数学上册人教版双色升级版》

$12×\frac {5}{16}= $
$\frac {5}{18}×27= $
$\frac {3}{17}×51= $
$\frac {3}{13}×\frac {26}{37}= $
$\frac {9}{14}×\frac {7}{9}= $
$\frac {23}{24}×\frac {8}{69}= $
$\frac {3}{5}×18×\frac {5}{9}= $
$16×\frac {5}{8}×\frac {1}{4}= $
$1-\frac {7}{10}×\frac {3}{28}= $
$28×\frac {4}{7}×\frac {3}{14}= $
$34×\frac {8}{17}×\frac {1}{2}= $
$\frac {7}{15}×60= $
$\frac {9}{56}×\frac {7}{36}= $

答案： 解析：这些题目都是分数乘法的基础练习，主要考查分数乘法的运算能力。
答案：
$12×\frac {5}{16}=\frac{15}{4}$
$\frac {5}{18}×27=\frac{15}{2}$
$\frac {3}{17}×51=9$
$\frac {3}{13}×\frac {26}{37}=\frac{6}{37}$
$\frac {9}{14}×\frac {7}{9}=\frac{1}{2}$
$\frac {23}{24}×\frac {8}{69}=\frac{1}{9}$
$\frac {3}{5}×18×\frac {5}{9}=6$
$16×\frac {5}{8}×\frac {1}{4}=\frac{5}{2}$
$1-\frac {7}{10}×\frac {3}{28}=\frac{37}{40}$
$28×\frac {4}{7}×\frac {3}{14}=\frac{24}{7}$（或 $3\frac{3}{7}$）
$34×\frac {8}{17}×\frac {1}{2}=8$
$\frac {7}{15}×60=28$
$\frac {9}{56}×\frac {7}{36}=\frac{1}{32}$

$\frac {7}{20}×15= $
$\frac {3}{10}×35= $
$\frac {5}{12}×24= $
$\frac {5}{6}×18= $
$\frac {4}{7}×5= $
$\frac {5}{16}×8= $
$\frac {5}{26}×5= $
$\frac {4}{11}×6= $
$\frac {2}{15}×12= $
$\frac {1}{40}×15= $
$\frac {2}{9}×27= $
$\frac {5}{21}×3= $
$\frac {1}{20}×25= $

答案： 分析：
这些题目都是基础的分数乘法口算题，主要考察分数与整数的乘法运算。
对于这类题目，可以直接将分数与整数相乘，得到结果。
答案为：
$\frac{7}{20} × 15 = \frac{7 × 15}{20} = \frac{105}{20} = \frac{21}{4}$ 或 $5.25$，
$\frac{3}{10} × 35 = \frac{3 × 35}{10} = \frac{105}{10} = \frac{21}{2}$ 或 $10.5$，
$\frac{5}{12} × 24 = \frac{5 × 24}{12} = 10$，
$\frac{5}{6} × 18 = \frac{5 × 18}{6} = 15$，
$\frac{4}{7} × 5 = \frac{4 × 5}{7} = \frac{20}{7}$，
$\frac{5}{16} × 8 = \frac{5 × 8}{16} = \frac{40}{16} = \frac{5}{2}$ 或 $2.5$，
$\frac{5}{26} × 5 = \frac{5 × 5}{26} = \frac{25}{26}$，
$\frac{4}{11} × 6 = \frac{4 × 6}{11} = \frac{24}{11}$，
$\frac{2}{15} × 12 = \frac{2 × 12}{15} = \frac{24}{15} = \frac{8}{5}$ 或 $1.6$，
$\frac{1}{40} × 15 = \frac{1 × 15}{40} = \frac{15}{40} = \frac{3}{8}$ 或 $0.375$，
$\frac{2}{9} × 27 = \frac{2 × 27}{9} = 6$，
$\frac{5}{21} × 3 = \frac{5 × 3}{21} = \frac{15}{21} = \frac{5}{7}$，
$\frac{1}{20} × 25 = \frac{1 × 25}{20} = \frac{25}{20} = \frac{5}{4}$ 或 $1.25$。

$280×\frac {3}{4}×\frac {1}{3}=$70
$300×\frac {2}{3}×\frac {1}{5}=$40
$140×\frac {5}{7}×\frac {3}{4}=$75
$100×\frac {1}{2}×\frac {3}{5}=$30
$640×\frac {7}{8}×\frac {3}{4}=$420
$360×\frac {5}{6}×\frac {2}{15}=$40
$180×\frac {2}{3}×\frac {7}{12}=$70
$480×\frac {3}{4}×\frac {3}{4}=$270
$360×\frac {7}{9}×\frac {3}{7}=$120
$400×\frac {3}{4}×\frac {5}{6}=$250
$390×\frac {5}{6}×\frac {2}{5}=$130
$450×\frac {2}{9}×\frac {3}{5}=$60
$560×\frac {1}{4}×\frac {2}{7}=$40

答案： 解析：这些题目都是分数连乘的口算题，我们只需要按照从左到右的顺序依次进行乘法运算即可。
答案：
$280×\frac {3}{4}×\frac {1}{3}$
$=210×\frac {1}{3}$
$=70$
$300×\frac {2}{3}×\frac {1}{5}$
$=200×\frac {1}{5}$
$=40$
$140×\frac {5}{7}×\frac {3}{4}$
$=100×\frac {3}{4}$
$=75$
$100×\frac {1}{2}×\frac {3}{5}$
$=50×\frac {3}{5}$
$=30$
$640×\frac {7}{8}×\frac {3}{4}$
$=560×\frac {3}{4}$
$=420$
$360×\frac {5}{6}×\frac {2}{15}$
$=300×\frac {2}{15}$
$=40$
$180×\frac {2}{3}×\frac {7}{12}$
$=120×\frac {7}{12}$
$=70$
$480×\frac {3}{4}×\frac {3}{4}$
$=360×\frac {3}{4}$
$=270$
$360×\frac {7}{9}×\frac {3}{7}$
$=280×\frac {3}{7}$
$=120$
$400×\frac {3}{4}×\frac {5}{6}$
$=300×\frac {5}{6}$
$=250$
$390×\frac {5}{6}×\frac {2}{5}$
$=325×\frac {2}{5}$
$=130$
$450×\frac {2}{9}×\frac {3}{5}$
$=100×\frac {3}{5}$
$=60$
$560×\frac {1}{4}×\frac {2}{7}$
$=140×\frac {2}{7}$
$=40$