Question

Cách vạn giúp mình mấy câu này.

Answer 1

Câu 1:

a:3/5-1/5=2/5

b: \(\dfrac{5}{7}+\dfrac{1}{2}:\dfrac{7}{4}-\dfrac{7}{5}=\dfrac{25-49}{35}+\dfrac{2}{7}=\dfrac{-24+10}{35}=\dfrac{-14}{35}=\dfrac{-2}{5}\)

c: \(=\dfrac{2}{9}\left(\dfrac{23}{4}-\dfrac{13}{4}+\dfrac{1}{2}\right)=\dfrac{2}{9}\cdot3=\dfrac{2}{3}\)