Question

1.Thuc hien phap tinh a) \((\)\(2\dfrac{3}{5}\)-\(3\dfrac{5}{9}\)\()\):\((\)\(3\dfrac{10}{21}\)-\(1\dfrac{3}{7}\)\()\) b) \(5\dfrac{1}{2}\)-\(14\dfrac{3}{7}\):\(\dfrac{9}{13}\)-\(3\dfrac{4}{7}\):\(\dfrac{9}{13}\)

Answer 1

a, \(\left(2\dfrac{3}{5}-3\dfrac{5}{9}\right):\left(3\dfrac{10}{21}-1\dfrac{3}{7}\right)\)

\(=\dfrac{-43}{45}:\dfrac{43}{21}=\dfrac{-43}{45}.\dfrac{21}{43}=\dfrac{-7}{15}\)

b, \(5\dfrac{1}{2}-14\dfrac{3}{7}:\dfrac{9}{13}-3\dfrac{4}{7}:\dfrac{9}{13}\)

\(=5\dfrac{1}{2}-14\dfrac{3}{7}.\dfrac{13}{9}-3\dfrac{4}{7}.\dfrac{13}{9}\)

\(=5\dfrac{1}{2}-\dfrac{13}{9}.\left(14\dfrac{3}{7}+\dfrac{4}{7}\right)\)

\(=5\dfrac{1}{2}-\dfrac{13}{9}.15=5\dfrac{1}{2}-\dfrac{65}{3}\)

\(=\dfrac{-97}{6}\)

Chúc bạn học tốt!!!

Answer 2

b, \(5\dfrac{1}{2}-14\dfrac{3}{7}:\dfrac{9}{13}-3\dfrac{4}{7}:\dfrac{9}{13}\)

\(=5\dfrac{1}{2}-\dfrac{13}{9}.\left(14\dfrac{3}{7}+3\dfrac{4}{7}\right)\)

\(=5\dfrac{1}{2}-\dfrac{13}{9}.18=5\dfrac{1}{2}-26\)

\(=\dfrac{-41}{2}\)

Chúc bạn học tốt!!!

Answer 3

\(\left(2\dfrac{3}{5}-3\dfrac{5}{9}\right):\left(3\dfrac{10}{21}-1\dfrac{3}{7}\right)\)

\(=\left(\dfrac{13}{5}-\dfrac{32}{9}\right):\left(\dfrac{73}{21}-\dfrac{10}{7}\right)\)

\(=-\dfrac{43}{45}:\dfrac{43}{21}=-\dfrac{21}{45}=-\dfrac{7}{15}\)

\(5\dfrac{1}{2}-14\dfrac{3}{7}:\dfrac{9}{13}-3\dfrac{4}{7}:\dfrac{9}{13}\)

\(=\dfrac{11}{2}-\left(14\dfrac{3}{7}+3\dfrac{4}{7}\right):\dfrac{9}{13}\)

\(=\dfrac{11}{2}-18:\dfrac{9}{13}\)

\(=\dfrac{11}{2}-26=\dfrac{-41}{2}\)