Решим примеры:
- $$12\frac{7}{20}+3\frac{3}{20}-4 = (12+3-4) + (\frac{7}{20} + \frac{3}{20}) = 11 + \frac{10}{20} = 11 + \frac{1}{2} = 11\frac{1}{2}$$
- $$24-8\frac{4}{11}-\frac{7}{11} = (24-8) - (\frac{4}{11} + \frac{7}{11}) = 16 - \frac{11}{11} = 16 - 1 = 15$$
Ответ: $$11\frac{1}{2}; 15$$