Thực hiện phép tính a) -9 1/3 . 5/9 + (-9 1/3) . 4/9 - 0,5 b) (0,7 + 3 1/5)

* Hướng dẫn giải

a) $-9\frac{1}{3}.\frac{5}{9}+\left(-9\frac{1}{3}\right).\frac{4}{9}-0,5$$=-9\frac{1}{3}.\left(\frac{5}{9}+\frac{4}{9}\right)-\frac{1}{2}=\frac{-28}{3}.1-\frac{1}{2}=\frac{-59}{6}$

b) $\left(0,7+3\frac{1}{5}\right):\frac{1}{8}+75\%$ $=\left(\frac{7}{10}+\frac{16}{5}\right):\frac{1}{8}+\frac{3}{4}=\frac{39}{10}.8+\frac{3}{4}$$=\frac{156}{5}+\frac{3}{4}=\frac{639}{20}=31\frac{19}{20}$