6/7x1/3
6/7- 1/3
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1/2x1/3+1/3x1/4+1/4x1/5+1/5x1/6+1/6x1/7+1/7x1/8+1/8x1/9
=7/18
\(\left(\dfrac{6}{7}+\dfrac{3}{14}\right):\dfrac{3}{7}\times\dfrac{1}{70}\)
\(=\left(\dfrac{12}{14}+\dfrac{3}{14}\right):\dfrac{3}{7}\times\dfrac{1}{70}\)
\(=\dfrac{15}{14}:\dfrac{3}{7}\times\dfrac{1}{70}\)
\(=\dfrac{15}{14}\times\dfrac{7}{3}\times\dfrac{1}{70}\)
\(=\dfrac{15\times7\times1}{14\times3\times70}\)
\(=\dfrac{105}{2940}=\dfrac{1}{28}\)
\(6\dfrac{1}{7}\times1\dfrac{6}{7}\)
\(=\dfrac{43}{7}\times\dfrac{13}{7}\)
\(=\dfrac{559}{49}\)
#Toru
\(6\dfrac{1}{7}\times1\dfrac{6}{7}=\dfrac{43}{7}\times\dfrac{13}{7}=\dfrac{559}{49}\)
\(\dfrac{1}{5}\times\dfrac{4}{7}+\dfrac{3}{7}\times\dfrac{1}{5}-\dfrac{1}{5}\)
\(=\dfrac{4}{35}+\dfrac{3}{35}-\dfrac{1}{5}\)
\(=\dfrac{7}{35}-\dfrac{1}{5}\)
\(=\dfrac{1}{5}-\dfrac{1}{5}\)
\(=0\)
\(=\dfrac{3}{7}\times\left(\dfrac{1}{5}+\dfrac{2}{3}-\dfrac{1}{8}\right)\\ =\dfrac{3}{7}\times\left(\dfrac{24}{5\times24}+\dfrac{2\times40}{3\times40}-\dfrac{15}{8\times15}\right)\\ =\dfrac{3}{7}\times\left(\dfrac{24+80-15}{120}\right)\\ =\dfrac{3}{7}\times\dfrac{89}{120}\\ =\dfrac{89}{280}\)
\(\dfrac{3}{7}\times\dfrac{1}{5}+\dfrac{2}{3}\times\dfrac{3}{7}-\dfrac{3}{7}\times\dfrac{1}{8}\)
\(=\dfrac{3}{7}\times\left(\dfrac{1}{5}+\dfrac{3}{7}-\dfrac{1}{8}\right)\)
\(=\dfrac{3}{7}\times\dfrac{56+120-35}{280}\)
\(=\dfrac{3}{7}\times\dfrac{141}{280}\)
\(=\dfrac{423}{1960}\)
2/7
11/21
2/7
11/21