Rút gọn
A = \(\frac{\frac{2}{39}-\frac{1}{15}-\frac{2}{153}}{\frac{1}{34}+\frac{3}{20}-\frac{3}{26}}\): \(\frac{1+\frac{2}{71}-\frac{5}{121}}{\frac{65}{121}-\frac{26}{71}-13}\)
B = ( \(\frac{112}{13.20}+\frac{112}{20.27}+\frac{112}{27.34}+...+\frac{112}{62.69}\)) :( \(-\frac{5}{9.13}-\frac{7}{9.25}-\frac{13}{19.25}-\frac{31}{19.69}\))