Question

tính giá trị biểu thức : (\(\frac{-5}{6}\) + \(\frac{-5}{12}\) +\(\frac{-5}{20}\) + ...+\(\frac{-5}{90}\) ) : (0.25 +\(\frac{7}{6}\) - \(2\frac{1}{3}\) ) : \(\frac{24}{33}\)

Answer 1

=> ( \(\frac{-5}{2.3}+\frac{-5}{3.4}+\frac{-5}{4.5}+.....+\frac{-5}{9.10}\)):(\(\frac{1}{4}+\frac{7}{6}-\frac{7}{3}\)):\(\frac{24}{33}\)

=>\(\frac{-5}{1}.\)(\(\frac{1}{2.3}+\frac{1}{3.4}+....+\frac{1}{9.10}\)):(\(\frac{3}{12}+\frac{14}{12}-\frac{28}{12}\)):\(\frac{24}{33}\)

=>-5.(\(\frac{1}{2}-\frac{1}{3}+\frac{1}{3}-\frac{1}{4}+...+\frac{1}{9}-\frac{1}{10}\)):(\(\frac{-11}{12}\)):\(\frac{24}{33}\)

=>-5.(\(\frac{1}{2}-\frac{1}{10}\)):\(\frac{-11}{10}\):\(\frac{24}{33}\)

=>-5.\(\frac{2}{5}\):\(\frac{-11}{10}:\frac{24}{33}\)

=>2:\(\frac{-11}{10}:\frac{24}{33}\)

=>\(\frac{-5}{2}\)