в) (2/15 + 7/12) : 30/43 - 2 : 2 1/2 · 5/32,

в)

$$(\frac{2}{15} + \frac{7}{12}) : \frac{30}{43} - 2 : 2 \frac{1}{2} \cdot \frac{5}{32} = (\frac{2 \cdot 4 + 7 \cdot 5}{60}) : \frac{30}{43} - 2 : \frac{5}{2} \cdot \frac{5}{32} = (\frac{8 + 35}{60}) : \frac{30}{43} - 2 \cdot \frac{2}{5} \cdot \frac{5}{32} = \frac{43}{60} : \frac{30}{43} - \frac{4}{5} \cdot \frac{5}{32} = \frac{43}{60} \cdot \frac{43}{30} - \frac{4 \cdot 5}{5 \cdot 32} = \frac{43 \cdot 43}{60 \cdot 30} - \frac{4}{32} = \frac{1849}{1800} - \frac{1}{8} = \frac{1849 - 1 \cdot 225}{1800} = \frac{1849 - 225}{1800} = \frac{1624}{1800} = \frac{812}{900} = \frac{406}{450} = \frac{203}{225}$$

Ответ: $$\frac{203}{225}$$