Perform the addition or subtraction:

Решение:

1. \( 3 \frac{3}{4} - 1 \frac{1}{4} = 3 \frac{3}{4} - 1 \frac{1}{4} = (3-1) + (\frac{3}{4} - \frac{1}{4}) = 2 + \frac{2}{4} = 2 \frac{1}{2} \)
2. \( 2 \frac{3}{4} - 1 \frac{1}{4} = 2 \frac{3}{4} - 1 \frac{1}{4} = (2-1) + (\frac{3}{4} - \frac{1}{4}) = 1 + \frac{2}{4} = 1 \frac{1}{2} \)
3. \( 6 \frac{4}{33} + 1 \frac{5}{33} = (6+1) + (\frac{4}{33} + \frac{5}{33}) = 7 + \frac{9}{33} = 7 \frac{3}{11} \)
4. \( 5 \frac{11}{25} + \frac{6}{25} = 5 + (\frac{11}{25} + \frac{6}{25}) = 5 + \frac{17}{25} = 5 \frac{17}{25} \)
5. \( 5 \frac{1}{3} - 4 \frac{2}{3} = 4 \frac{4}{3} - 4 \frac{2}{3} = (4-4) + (\frac{4}{3} - \frac{2}{3}) = \frac{2}{3} \)
6. \( 6 \frac{14}{17} + 1 \frac{6}{17} = (6+1) + (\frac{14}{17} + \frac{6}{17}) = 7 + \frac{20}{17} = 7 + 1 \frac{3}{17} = 8 \frac{3}{17} \)
7. \( 7 \frac{4}{5} - 6 \frac{4}{5} = (7-6) + (\frac{4}{5} - \frac{4}{5}) = 1 + 0 = 1 \)
8. \( \frac{7}{71} - \frac{9}{71} = \frac{7-9}{71} = -\frac{2}{71} \)
9. \( 8 \frac{8}{9} + 8 \frac{7}{9} = (8+8) + (\frac{8}{9} + \frac{7}{9}) = 16 + \frac{15}{9} = 16 + 1 \frac{6}{9} = 17 \frac{2}{3} \)