Tính giá trị biểu thức a) 11/22 - 3/16 . 8/18 b) 2/3 + 4/5 . 10/4

* Hướng dẫn giải

a) $\frac{11}{22}-\frac{3}{16}.\frac{8}{18}$

$\begin{array}{l}=\frac{1}{2}-\frac{1}{12}\\ =\frac{5}{12}\end{array}$

b) $\frac{2}{3}+\frac{4}{5}.\frac{10}{4}$

$\begin{array}{l}=\frac{2}{3}+2\\ =2\frac{2}{3}\end{array}$

c) $\left(\frac{1}{3}+\frac{4}{6}\right).\left(\frac{2}{7}+\frac{9}{14}\right)$

$\begin{array}{l}=\left(\frac{1}{3}+\frac{4}{6}\right).\left(\frac{2}{7}+\frac{9}{14}\right)\\ =\left(\frac{1}{3}+\frac{2}{3}\right).\left(\frac{4}{14}+\frac{9}{14}\right)\\ =1.\frac{13}{14}=\frac{13}{14}\end{array}$