3) 2 1/2 · 48 - 3 2/3 : 18/5 + 5 1/2 : 5 7/36

Решение:

3) \( 2 \frac{1}{2} \cdot 48 - 3 \frac{2}{3} : \frac{18}{5} + 5 \frac{1}{2} : 5 \frac{7}{36} \)

1. \( 2 \frac{1}{2} \cdot 48 = \frac{5}{2} \cdot 48 = 5 \cdot 24 = 120 \)
2. \( 3 \frac{2}{3} : \frac{18}{5} = \frac{11}{3} : \frac{18}{5} = \frac{11}{3} \cdot \frac{5}{18} = \frac{55}{54} \)
3. \( 5 \frac{1}{2} : 5 \frac{7}{36} = \frac{11}{2} : \frac{187}{36} = \frac{11}{2} \cdot \frac{36}{187} = \frac{11 \u00B7 36}{2 \u00B7 187} = \frac{11 \u00B7 18}{187} = \frac{198}{187} \)
4. \( 120 - \frac{55}{54} + \frac{198}{187} \)
5. \( 120 - 1 \frac{1}{54} + 1 \frac{11}{187} \)
6. \( 120 - 1 - \frac{1}{54} + 1 + \frac{11}{187} \)
7. \( 120 - \frac{1}{54} + \frac{11}{187} \)
8. \( 120 - \frac{1 \u00B7 187}{54 \u00B7 187} + \frac{11 \u00B7 54}{187 \u00B7 54} = 120 - \frac{187}{10098} + \frac{594}{10098} \)
9. \( 120 + \frac{594 - 187}{10098} = 120 + \frac{407}{10098} \)
10. \( \frac{407}{10098} = \frac{37 \u00B7 11}{37 \u00B7 273} = \frac{11}{273} \)
11. \( 120 + \frac{11}{273} \)

Ответ: \( 120 \frac{11}{273} \).