Question

Answer 1

Câu 1: \(a,\dfrac{1}{3}+\dfrac{5}{7}+\dfrac{2}{3}+\dfrac{9}{7}=\left(\dfrac{1}{3}+\dfrac{2}{3}\right)+\left(\dfrac{5}{7}+\dfrac{9}{7}\right)=1+2=3\)

\(b,2^2.\dfrac{3}{16}-\dfrac{1}{8}=4.\dfrac{3}{16}-\dfrac{1}{8}=\dfrac{3}{4}-\dfrac{1}{8}=\dfrac{5}{8}\)

\(39\dfrac{1}{3}:\dfrac{4}{5}-19\dfrac{1}{3}:\dfrac{4}{5}=\dfrac{118}{3}:\dfrac{4}{5}-\dfrac{58}{3}:\dfrac{4}{5}=\left(\dfrac{118}{3}-\dfrac{58}{3}\right):\dfrac{4}{5}=20:\dfrac{4}{5}=20.\dfrac{5}{4}=25\)

\(d,\dfrac{3}{4}+\dfrac{1}{8}.\left|-\dfrac{2}{3}\right|=\dfrac{3}{4}+\dfrac{1}{8}.\dfrac{2}{3}=\dfrac{3}{4}+\dfrac{1}{12}=\dfrac{5}{6}\)