Question

5/6 x 4/5 + 4/5 x 2/12 ( Tính nhanh )

Answer 1

\(\dfrac{4}{5}\times\left(\dfrac{5}{6}+\dfrac{2}{12}\right)=\dfrac{4}{5}\times\left(\dfrac{10}{12}+\dfrac{2}{12}\right)=\dfrac{4}{5}\times\dfrac{12}{12}=\dfrac{4}{5}\times1=\dfrac{4}{5}\times\dfrac{1}{1}=\dfrac{4}{5}\)

Answer 2

\(=\dfrac{5}{6}\times\dfrac{4}{5}+\dfrac{4}{5}\times\dfrac{1}{6}=\left(\dfrac{5}{6}+\dfrac{1}{6}\right)\times\dfrac{4}{5}=\dfrac{6}{6}\times\dfrac{4}{5}=1\times\dfrac{4}{5}=\dfrac{4}{5}\)

Answer 3

   5/6 x 4/5 + 4/5 x 2/12

= 4/5 x (5/6 + 2/12)

= 4/5 x (10/12 + 2/12)

= 4/5 x 1

= 4/5