1) Tính hợp lí:A = \(\frac{5}{12}\cdot\frac{1}{7}+\frac{5}{12}\cdot\frac{3}{7}+\frac{5}{12}\cdot\frac{2}{7}\)B = \(\frac{9}{8}\cdot\frac{-5}{13}+\frac{-5}{8}\cdot\frac{4}{13}\)2)...
Đọc tiếp
1) Tính hợp lí:
A = \(\frac{5}{12}\cdot\frac{1}{7}+\frac{5}{12}\cdot\frac{3}{7}+\frac{5}{12}\cdot\frac{2}{7}\)
B = \(\frac{9}{8}\cdot\frac{-5}{13}+\frac{-5}{8}\cdot\frac{4}{13}\)
2) Tính:
a) \(\left(\frac{2}{3}+\frac{1}{5}-\frac{4}{9}\right):\left(\frac{1}{3}+\frac{2}{5}-\frac{6}{9}\right)\)
b) \(\frac{1}{2}\cdot\frac{3}{5}+\frac{4}{7}:\frac{4}{5}-\frac{1}{70}\)
