ДИАМЕТР СТВОЛА (М) (2$$\frac{3}{5} \cdot \frac{20}{39} + 6\frac{7}{12}):(5\frac{5}{72} + 8,125) + 0,04=

Выполним вычисление диаметра ствола:

1) $$2\frac{3}{5} \cdot \frac{20}{39} = \frac{13}{5} \cdot \frac{20}{39} = \frac{1}{1} \cdot \frac{4}{3} = \frac{4}{3} = 1\frac{1}{3}$$

2) $$6\frac{7}{12} = \frac{79}{12}$$

3) $$1\frac{1}{3} + \frac{79}{12} = \frac{4}{3} + \frac{79}{12} = \frac{4 \cdot 4}{3 \cdot 4} + \frac{79}{12} = \frac{16}{12} + \frac{79}{12} = \frac{95}{12}$$

4) $$5\frac{5}{72} = \frac{365}{72}$$

5) $$8,125 = 8\frac{125}{1000} = 8\frac{1}{8} = \frac{65}{8}$$

6) $$\frac{365}{72} + \frac{65}{8} = \frac{365}{72} + \frac{65 \cdot 9}{8 \cdot 9} = \frac{365}{72} + \frac{585}{72} = \frac{950}{72} = \frac{475}{36}$$

7) $$\frac{95}{12} : \frac{475}{36} = \frac{95}{12} \cdot \frac{36}{475} = \frac{1}{1} \cdot \frac{3}{5} = \frac{3}{5} = 0,6$$

8) $$0,6 + 0,04 = 0,64$$

Ответ: 0,64