Математика 40 баллов (-6 7/8+1,375-5 1/2*0,73):(-1,73)

Решите задачу:

$( - 6 \frac{7}{8} + 1.375 - 5 \frac{1}{2} \times 0.73) \div ( - 1.73) = 5.5\: \: \: \\ 1) \: \: \: 5 \frac{1}{2} \times 0.73 = 5.5 \times 0.73 = 4.015 \\ 2) \: \: \: - 6 \frac{7}{8} + 1.375 = - 6.875 + 1.375 = - 5.5\\ 3) \: \: \: -5.5 - 4.015 = - 9.515 \\ 4) \: \: \: - 9.515 \div ( - 1.73) = \frac{9515}{1000} \times \frac{100}{173} = \frac{1903}{2 \times 173} = \frac{11}{2} = 5 \frac{1}{2} = 5.5$