Ответ:

1) \(6\frac{1}{4}\cdot8-3\frac{2}{3}=\frac{25}{4}\cdot8-\frac{11}{3}=50-\frac{11}{3}=46\frac{1}{3}\).

2) \(6-\frac{1}{2}+2\frac{2}{5}\cdot4\frac{7}{12}=\frac{11}{2}+\frac{12}{5}\cdot\frac{55}{12}=\frac{11}{2}+11=16\frac{1}{2}\).

Ответ: \(46\frac{1}{3};\ 16\frac{1}{2}\).