Question

8．在○里填上“＞”“＜”或“=”．
$\frac{8}{9}$×$\frac{8}{9}$○$\frac{8}{9}$
$\frac{5}{8}$×$\frac{7}{5}$○$\frac{5}{8}$
$\frac{6}{5}$×$\frac{3}{4}$○$\frac{6}{5}$
$\frac{6}{7}$×$\frac{5}{9}$○$\frac{6}{7}$
$\frac{10}{9}$×$\frac{9}{10}$○$\frac{10}{9}$
$\frac{7}{5}$×$\frac{2}{3}$○$\frac{7}{5}$×$\frac{3}{2}$．

Answer 1

分析 一個數(shù)（0除外）乘小于1的數(shù)，積小于這個數(shù)；一個數(shù)（0除外）乘大于1的數(shù)，積大于這個數(shù)；據(jù)此解答．

解答 解：$\frac{8}{9}$×$\frac{8}{9}$＜$\frac{8}{9}$
$\frac{5}{8}$×$\frac{7}{5}$＞$\frac{5}{8}$
$\frac{6}{5}$×$\frac{3}{4}$＜$\frac{6}{5}$
$\frac{6}{7}$×$\frac{5}{9}$＜$\frac{6}{7}$
$\frac{10}{9}$×$\frac{9}{10}$＜$\frac{10}{9}$
$\frac{7}{5}$×$\frac{2}{3}$＜$\frac{7}{5}$×$\frac{3}{2}$．
故答案為：＜，＞，＜，＜，＜，＜．

點評 此題考查了不用計算判斷因數(shù)與積之間大小關系的方法．