Question

Answer 1

Bài 1:

a. \(\dfrac{5}{12}+\dfrac{3}{4}+\dfrac{1}{3}=\dfrac{5}{12}+\dfrac{9}{12}+\dfrac{4}{12}=\dfrac{3}{2}\)

b. \(\dfrac{1}{4}+\dfrac{3}{7}+\dfrac{11}{14}=\dfrac{7}{28}+\dfrac{12}{28}+\dfrac{22}{28}=\dfrac{41}{28}\)

Bài 2:

a. \(x:\dfrac{3}{8}=\dfrac{5}{6}\)

\(\Rightarrow x=\dfrac{5}{6}\) x \(\dfrac{3}{8}\)

\(\Rightarrow x=\dfrac{5}{16}\)

b. \(\dfrac{23}{69}-x=\dfrac{17}{153}\)

\(\dfrac{1}{3}-x=\dfrac{1}{9}\)

\(\Rightarrow x=\dfrac{1}{3}-\dfrac{1}{9}\)

\(\Rightarrow x=\dfrac{3}{9}-\dfrac{1}{9}\)

\(\Rightarrow x=\dfrac{2}{9}\)