《2025年计算高手六年级数学上册苏教版》

一、直接写出得数。
$12× \frac {5}{6}= $
$\frac {1}{6}× \frac {6}{7}= $
$\frac {4}{25}× 100= $
$\frac {7}{18}× 16= $
$\frac {5}{9}× 8= $
$\frac {18}{25}× 15= $
$\frac {7}{25}× \frac {15}{14}= $
$\frac {7}{50}× \frac {10}{7}= $
$\frac {9}{20}× \frac {10}{9}= $
$\frac {7}{26}× \frac {2}{3}= $
$\frac {7}{16}× \frac {32}{21}= $
$\frac {4}{5}× \frac {15}{16}= $
$\frac {7}{24}× \frac {8}{7}= $
$\frac {2}{5}× \frac {3}{4}= $
$\frac {7}{18}× \frac {1}{7}= $
$\frac {2}{3}× \frac {15}{16}= $
$\frac {5}{6}× \frac {3}{4}= $
$\frac {4}{13}× \frac {13}{16}= $
$\frac {2}{3}× \frac {3}{5}= $
$\frac {4}{7}× \frac {1}{2}= $
$\frac {5}{8}× \frac {2}{5}= $

答案： 10 $\frac{1}{7}$ 16 $\frac{56}{9}$ $\frac{40}{9}$ $\frac{54}{5}$ $\frac{3}{10}$ $\frac{1}{5}$ $\frac{1}{2}$ $\frac{7}{39}$ $\frac{2}{3}$ $\frac{3}{4}$ $\frac{1}{3}$ $\frac{3}{10}$ $\frac{1}{18}$ $\frac{5}{8}$ $\frac{5}{8}$ $\frac{1}{4}$ $\frac{2}{5}$ $\frac{2}{7}$ $\frac{1}{4}$

二、看图列式计算。

答案： 1. 32×$\frac{3}{4}$×$\frac{2}{3}$=16(个) 2. 8×$\frac{9}{2}$=36(岁)

三、$\frac {1}{2}×\frac {3}{4}×\frac {5}{6}×\frac {7}{8}×\frac {9}{10}×\frac {11}{12}×\frac {13}{14}×\frac {15}{16}$的积与0.25比较,哪个大?

答案： 0.25大 提示 设A=$\frac{1}{2}×\frac{3}{4}×\frac{5}{6}×\frac{7}{8}×\frac{9}{10}×\frac{11}{12}×\frac{13}{14}×\frac{15}{16}$,B=$\frac{2}{3}×\frac{4}{5}×\frac{6}{7}×\frac{8}{9}×\frac{10}{11}×\frac{12}{13}×\frac{14}{15}$,则A×B=$\frac{1}{2}×\frac{2}{3}×\frac{3}{4}×\frac{4}{5}×\frac{5}{6}×\frac{6}{7}×\frac{7}{8}×\frac{8}{9}×\frac{9}{10}×\frac{10}{11}×\frac{11}{12}×\frac{12}{13}×\frac{13}{14}×\frac{14}{15}×\frac{15}{16}$=$\frac{1}{16}=(\frac{1}{4})^{2}$。因为A的前7项都分别小于B的对应项,A的最后一项$\frac{15}{16}＜1$,所以A＜B,再由$(\frac{1}{4})^{2}=A×B＞A^{2}$,可知$\frac{1}{4}＞A$,即0.25＞$\frac{1}{2}×\frac{3}{4}×\frac{5}{6}×\frac{7}{8}×\frac{9}{10}×\frac{11}{12}×\frac{13}{14}×\frac{15}{16}$。