\(\dfrac{2}{7}.\dfrac{4}{5}+\dfrac{3}{5}.\dfrac{2}{7}-\dfrac{1}{5}\)
\(=\dfrac{8}{35}+\dfrac{6}{35}-\dfrac{1}{5}\)
\(=\dfrac{2}{5}-\dfrac{1}{5}\)
\(=\dfrac{1}{5}\)
Đúng 0
Bình luận (0)
\(\dfrac{2}{7}\cdot\dfrac{4}{5}+\dfrac{3}{5}\cdot\dfrac{2}{7}-\dfrac{1}{5}=\dfrac{8}{35}+\dfrac{6}{35}-\dfrac{7}{35}=\dfrac{8+6-7}{35}=\dfrac{7}{35}=\dfrac{1}{5}\)
Đúng 0
Bình luận (0)