Question

1/4+1/5+3/4+2/5 bằng bao nhiêu vậy giúp mình với

Answer 1

\(\dfrac{1}{4}+\dfrac{1}{5}+\dfrac{3}{4}+\dfrac{2}{5}\)

\(=\left(\dfrac{1}{4}+\dfrac{3}{4}\right)+\left(\dfrac{1}{5}+\dfrac{2}{5}\right)\)

\(=1+\dfrac{3}{5}=\dfrac{8}{5}\)

Answer 2

\(\dfrac{1}{4}+\dfrac{1}{5}+\dfrac{3}{4}+\dfrac{2}{5}\\ =\left(\dfrac{1}{4}+\dfrac{3}{4}\right)+\left(\dfrac{1}{5}+\dfrac{2}{5}\right)\\ =\dfrac{1+3}{4}+\dfrac{1+2}{5}\\ =\dfrac{4}{4}+\dfrac{3}{5}\\ =1+\dfrac{3}{5}\\ =\dfrac{5}{5}+\dfrac{3}{5}\\ =\dfrac{8}{5}\)