Question

Rút gọn rồi tính: A) 5/10_2/15 B) 5/20_1/6 C) 6/18_6/24 D) 5/9_3/12

Answer 1

A) \(\dfrac{5}{10}\) - \(\dfrac{2}{15}\) = \(\dfrac{1}{2}\) -\(\dfrac{2}{15}\) =\(\dfrac{15}{30}\) -\(\dfrac{4}{30}\) =\(\dfrac{11}{30}\)

B)\(\dfrac{5}{20}\)-\(\dfrac{1}{6}\)=\(\dfrac{1}{4}\)-\(\dfrac{1}{6}\)=\(\dfrac{6}{24}\)-\(\dfrac{4}{24}\)=\(\dfrac{2}{24}\)=\(\dfrac{1}{12}\)

C)\(\dfrac{6}{18}\)-\(\dfrac{6}{24}\)=\(\dfrac{1}{3}\)-\(\dfrac{1}{4}\)=\(\dfrac{4}{12}\)-\(\dfrac{3}{12}\)=\(\dfrac{1}{12}\)

D)\(\dfrac{5}{9}\)-\(\dfrac{3}{12}\)=\(\dfrac{5}{9}\)-\(\dfrac{1}{4}\)=\(\dfrac{20}{36}\)-\(\dfrac{9}{36}\)=\(\dfrac{11}{36}\)