\(A=\frac{15}{11}-\frac{8}{13}+\frac{7}{11}-\frac{5}{13}=\left(\frac{15}{11}+\frac{7}{11}\right)-\left(\frac{8}{13}+\frac{5}{13}\right)=\frac{22}{11}-\frac{13}{13}=2-1=1\)
\(A=\frac{15}{11}-\frac{8}{13}+\frac{7}{11}-\frac{5}{13}\)
\(=>A=\left(\frac{15}{11}+\frac{7}{11}\right)-\left(\frac{8}{13}+\frac{5}{13}\right)\)
\(=>A=\frac{22}{11}-\frac{13}{13}=2-1=1\)