\(\dfrac{15}{11}+\dfrac{8}{13}-\dfrac{4}{11}+\dfrac{18}{13}\)
\(=\left(\dfrac{15}{11}-\dfrac{4}{11}\right)+\left(\dfrac{8}{13}+\dfrac{18}{13}\right)\)
\(=1+2\)
\(=3\)
\(\dfrac{15}{11}+\dfrac{8}{13}-\dfrac{4}{11}+\dfrac{18}{13}=\left(\dfrac{15}{11}-\dfrac{4}{11}\right)+\left(\dfrac{8}{13}+\dfrac{18}{13}\right)=\dfrac{11}{11}+\dfrac{26}{13}=1+2=3\)