Question

tính nhanh 

a) \(\dfrac{5}{11}\)+\(\dfrac{1}{4}\)+ \(\dfrac{2}{5}\)

Answer 1

a: =5/11+5/20+8/20

=5/11+13/20

=100/220+143/220=243/220

Answer 2

 

\(\dfrac{5}{11}+\dfrac{1}{4}+\dfrac{2}{5}=\dfrac{5}{11}+\left(\dfrac{1}{4}+\dfrac{2}{5}\right)=\dfrac{5}{11}+\dfrac{13}{20}=\dfrac{100}{220}+\dfrac{143}{220}=\dfrac{243}{220}\)