4.Вычислите: 1)-0,72------------0,032)-7 -9------------ 43)40---------1/10-1/5

Решите задачу:

$1) \frac{ - 0.72}{ - 0.003} = 240 \\ 2) \frac{ - 7 - 9}{4} = \frac{ - 16}{4} = \frac{ - 4}{1} = - 4 \\ 3) \frac{40}{ \frac{1}{10} - \frac{1}{5} } = \frac{40}{ \frac{1}{10} - \frac{1}{5} = \frac{1 - 2}{10} = \frac{ - 1}{10} } = \frac{40}{1} \times \frac{10}{ - 1} = \frac{40}{ - 1} = - 40$