Question

 A,\(\dfrac{1}{6}\)+\(\dfrac{7}{3}\)-\(\dfrac{1}{2}\)                                 B, (-1\(\dfrac{5}{8}\))+1,25:(1-\(\dfrac{9}{4}\))

Answer 1

\(a,\dfrac{1}{6}+\dfrac{7}{3}-\dfrac{1}{2}\\ =\dfrac{1}{6}+\dfrac{14}{6}-\dfrac{3}{6}\\ =\dfrac{12}{6}\\ =2\\ b,\left(-1\dfrac{5}{8}\right)+1,25:\left(1-\dfrac{9}{4}\right)\\ =\dfrac{-13}{8}+\dfrac{5}{4}:\dfrac{5}{4}\\ =\dfrac{-13}{8}+1\\ =\dfrac{-13}{8}+\dfrac{8}{8}\\ =\dfrac{5}{8}\)

Answer 2

A) \(\dfrac{1}{6}+\dfrac{7}{3}-\dfrac{1}{2}\)

Quy đồng: 

\(\dfrac{7}{3}=\dfrac{14}{6}\)

\(\dfrac{1}{2}=\dfrac{3}{6}\)

\(\dfrac{1}{6}=\dfrac{1}{6}\)

\(\dfrac{1}{6}+\dfrac{14}{6}-\dfrac{3}{6}=\dfrac{12}{6}\)

Rút gọn: \(\dfrac{12}{6}=\dfrac{12\div6}{6\div6}=2\)