Question

[Nguyễn Nhật Giang]

Tính nhanh:

a) \(\frac{-3}{7}\)+\(\frac{15}{26}\)- (\(\frac{2}{13}\)-\(\frac{3}{7}\))

b) 2.\(\frac{3}{7}\)+ (\(\frac{2}{9}\)- 1\(\frac{3}{7}\)) - \(\frac{5}{3}\):\(\frac{1}{9}\)

c) \(\frac{-11}{23}\).\(\frac{6}{7}\)+\(\frac{8}{7}\).\(\frac{-11}{23}\)-\(\frac{1}{23}\)

d) (\(\frac{377}{-231}\)-\(\frac{123}{89}\)+\(\frac{34}{791}\)) . (\(\frac{1}{6}\)-\(\frac{1}{8}\)-\(\frac{1}{24}\))

Answer 1

[Lê Nguyễn Hằng]

a)\(=\frac{-3}{7}+\frac{15}{26}-\frac{2}{13}+\frac{3}{7}\)

\(=\left(\frac{-3}{7}+\frac{3}{7}\right)-\left(\frac{15}{26}+\frac{2}{13}\right)\)

\(=0-\frac{19}{26}\)

\(=-\frac{19}{26}\)

Answer 2

[Lê Nguyễn Hằng]

c)\(=\frac{-11}{23}.\left(\frac{6}{7}+\frac{8}{7}\right)-\frac{1}{23}\)

\(=\frac{-11}{23}.2-\frac{1}{23}\)

\(=\frac{-22}{23}-\frac{1}{23}\)

\(=-1\)