Question

15£®¼ÆËã

$\frac{7}{51}$¡Á$\frac{17}{28}$¡Á$\frac{3}{5}$	£¨4$\frac{1}{2}$-2$\frac{2}{3}$£©¡Â$\frac{3}{55}$	$\frac{21}{25}$¡Â4¡Â$\frac{3}{10}$
$\frac{7}{9}$¡Â1$\frac{1}{2}$¡Á2$\frac{2}{5}$	£¨1$\frac{1}{3}$-$\frac{2}{5}$£©¡Â4$\frac{2}{3}$	72¡Á£¨$\frac{5}{9}$-$\frac{2}{7}$£©¡Á35£®

Answer 1

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½â´ð ½â£º£¨1£©$\frac{7}{51}$¡Á$\frac{17}{28}$¡Á$\frac{3}{5}$
=$\frac{1}{12}¡Á\frac{3}{5}$
=$\frac{1}{20}$£»

£¨2£©£¨4$\frac{1}{2}$-2$\frac{2}{3}$£©¡Â$\frac{3}{55}$
=$1\frac{5}{6}¡Â\frac{3}{55}$
=$\frac{11}{6}¡Á\frac{55}{3}$
=$\frac{605}{18}$£»

£¨3£©$\frac{21}{25}$¡Â4¡Â$\frac{3}{10}$
=$\frac{21}{25}¡Á\frac{1}{4}¡Á\frac{10}{3}$
=$\frac{7}{10}$£»

£¨4£©$\frac{7}{9}$¡Â1$\frac{1}{2}$¡Á2$\frac{2}{5}$
=$\frac{7}{9}¡Á\frac{2}{3}¡Á\frac{12}{5}$
=$\frac{56}{45}$£»

£¨5£©£¨1$\frac{1}{3}$-$\frac{2}{5}$£©¡Â4$\frac{2}{3}$  
=$\frac{14}{15}¡Á\frac{3}{14}$
=$\frac{1}{5}$£®

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