Question

[=)) người ko tên bí ẩn]

mình cần giải gấp , chủ đề ko liên quan vì đề cô cho

Answer 1

[chuche]

\(a,\left(\dfrac{5}{6}+\dfrac{2}{3}\right)\times\dfrac{3}{4}\\ =\left(\dfrac{5}{6}+\dfrac{4}{6}\right)\times\dfrac{3}{4}\\ =\dfrac{9}{6}\times\dfrac{3}{4}\\ =\dfrac{3}{2}\times\dfrac{3}{4}\\ =\dfrac{9}{8}\\ b,\dfrac{7}{3}\times\dfrac{3}{4}+\dfrac{7}{3}\times\dfrac{4}{5}\\ =\dfrac{7}{3}\times\left(\dfrac{3}{4}+\dfrac{4}{5}\right)\\ =\dfrac{7}{3}\times\left(\dfrac{15}{20}+\dfrac{16}{20}\right)\\ =\dfrac{7}{3}\times\dfrac{31}{20}\\ =\dfrac{217}{60}\\ c,\dfrac{7}{5}+\dfrac{4}{3}+\dfrac{7}{5}+\dfrac{4}{3}\\ =\left(\dfrac{7}{5}+\dfrac{7}{5}\right)+\left(\dfrac{4}{3}+\dfrac{4}{3}\right)\\ =\dfrac{14}{5}+\dfrac{8}{3}\\ =\dfrac{42}{15}+\dfrac{40}{15}\\ =\dfrac{82}{15}\)

Answer 2

[chuche]

từ từ :")) cía nii cách 1