1. 7 1/4 + 3 5/6

1. $7 \frac{1}{4} + 3 \frac{5}{6} = 7 \frac{3}{12} + 3 \frac{10}{12} = 10 \frac{13}{12} = 11 \frac{1}{12}$ 2. $9 \frac{2}{5} - 4 \frac{1}{3} = 9 \frac{6}{15} - 4 \frac{5}{15} = 5 \frac{1}{15}$ 3. $8 \frac{3}{8} + 2 \frac{1}{6} = 8 \frac{9}{24} + 2 \frac{4}{24} = 10 \frac{13}{24}$ 4. $12 - 5 \frac{4}{7} = 11 \frac{7}{7} - 5 \frac{4}{7} = 6 \frac{3}{7}$ 5. $6 \frac{1}{2} - 3 \frac{4}{5} = 6 \frac{5}{10} - 3 \frac{8}{10} = 5 \frac{15}{10} - 3 \frac{8}{10} = 2 \frac{7}{10}$ 6. $4 \frac{7}{9} + 1 \frac{1}{2} = 4 \frac{14}{18} + 1 \frac{9}{18} = 5 \frac{23}{18} = 6 \frac{5}{18}$ 7. $10 \frac{3}{10} - 6 \frac{3}{4} = 10 \frac{6}{20} - 6 \frac{15}{20} = 9 \frac{26}{20} - 6 \frac{15}{20} = 3 \frac{11}{20}$ 8. $5 \frac{2}{3} + 4 \frac{4}{7} = 5 \frac{14}{21} + 4 \frac{12}{21} = 9 \frac{26}{21} = 10 \frac{5}{21}$ 9. $15 - 8 \frac{5}{12} = 14 \frac{12}{12} - 8 \frac{5}{12} = 6 \frac{7}{12}$ 10. $11 \frac{1}{6} - 7 \frac{5}{8} = 11 \frac{4}{24} - 7 \frac{15}{24} = 10 \frac{28}{24} - 7 \frac{15}{24} = 3 \frac{13}{24}$ 11. $3 \frac{4}{15} + 2 \frac{3}{10} = 3 \frac{8}{30} + 2 \frac{9}{30} = 5 \frac{17}{30}$ 12. $9 \frac{5}{14} - 2 \frac{1}{2} = 9 \frac{5}{14} - 2 \frac{7}{14} = 8 \frac{19}{14} - 2 \frac{7}{14} = 6 \frac{12}{14} = 6 \frac{6}{7}$ 13. $8 - 3 \frac{7}{11} = 7 \frac{11}{11} - 3 \frac{7}{11} = 4 \frac{4}{11}$ 14. $6 \frac{5}{6} + 7 \frac{3}{8} = 6 \frac{20}{24} + 7 \frac{9}{24} = 13 \frac{29}{24} = 14 \frac{5}{24}$ 15. $14 \frac{2}{9} - 5 \frac{5}{6} = 14 \frac{4}{18} - 5 \frac{15}{18} = 13 \frac{22}{18} - 5 \frac{15}{18} = 8 \frac{7}{18}$ 16. $4 \frac{3}{4} + 8 \frac{2}{5} = 4 \frac{15}{20} + 8 \frac{8}{20} = 12 \frac{23}{20} = 13 \frac{3}{20}$ 17. $13 \frac{1}{12} - 4 \frac{7}{15} = 13 \frac{5}{60} - 4 \frac{28}{60} = 12 \frac{65}{60} - 4 \frac{28}{60} = 8 \frac{37}{60}$ 18. $7 \frac{5}{18} + 3 \frac{1}{4} = 7 \frac{10}{36} + 3 \frac{9}{36} = 10 \frac{19}{36}$ 19. $20 - 11 \frac{8}{9} = 19 \frac{9}{9} - 11 \frac{8}{9} = 8 \frac{1}{9}$