\(\dfrac{3}{4}+\dfrac{1}{3}+\dfrac{2}{5}=\dfrac{45}{60}+\dfrac{20}{60}+\dfrac{24}{60}=\dfrac{89}{60}\)
\(\dfrac{3}{4}+\dfrac{1}{3}+\dfrac{2}{5}=\dfrac{9}{12}+\dfrac{4}{12}+\dfrac{2}{5}=\dfrac{13}{12}+\dfrac{2}{5}=\dfrac{65}{60}+\dfrac{24}{60}=\dfrac{89}{60}\)
3/4+1/3+2/5=45/60+20/60+24/60=89/60
Chúc b học tốt~