Step-by-step explanation:1.) [tex] \frac{3}{9} + \frac{1}{9} + \frac{4}{9} = \frac{8}{9} [/tex]2.) [tex] \frac{5}{8} + \frac{7}{8} = \frac{12}{8} \\ \frac{12 \div 4}{8 \div 4} = \frac{3}{2} [/tex]3.) [tex] \frac{9}{20} + \frac{7}{20} = \frac{16}{20} \\ \frac{16 \div 4}{20 \div 4} = \frac{4}{5} + 8 = 8 \frac{4}{5} [/tex]4.)[tex]9 + 4 + 2 = 15 \\ \frac{5}{8} + \frac{3}{8} = \frac{8}{8} = 1 \\ 15 + 1 = 16[/tex]5.) [tex]12 + 10 = 22 \\ \frac{5}{14} + \frac{7}{14} + \frac{3}{14} = \frac{15}{14 \\ } \\ since \: it \: is \: a \: improper \: fraction \: convert \: it \: to \: a \: mixed \: number \\ \frac{15}{14} = 1 \frac{1}{14} \\ 22 + 1 \frac{1}{14} = 23 \frac{1}{14} [/tex]6.) [tex]12 \frac{1}{4} = \frac{12 \times 4 + 1}{4} = \frac{49}{4} \\ 6 \frac{3}{4} = \frac{6 \times 4 + 3}{4} = \frac{27}{4} \\ \frac{49}{4} - \frac{27}{4} = \frac{22}{4} = \frac{11}{2} \\ convert \: it \: back \: to \\ a \: mixed \: number \\ \frac{11}{2} = 5 \frac{1}{2} [/tex]7.) [tex]8 = \frac{8 \times 3}{3} = \frac{24}{3} \\ \frac{24}{3} - \frac{2}{3} = \frac{22}{3} = 7 \frac{1}{3} [/tex]8.) [tex]4 \frac{2}{5} = \frac{4 \times 5 + 2}{5} = \frac{22}{5} \\ 12 = \frac{12 \times 5}{5} = \frac{60}{5} \\ \frac{60}{5} - \frac{22}{5} = \frac{38 }{5} \\ \frac{38}{5} = 7 \frac{3}{5} [/tex]8.) [tex] \frac{150 \times 5 + 3}{5} = \frac{753}{5} \\ \frac{129 \times 5 + 4}{5} = \frac{649}{5} \\ 10 = \frac{10 \times 5}{5} = \frac{50}{5} \\ \frac{753}{5} - \frac{50}{5} = \frac{703}{5} \\ \frac{703}{5} - \frac{649}{5} = \frac{54}{5} = 10 \frac{4}{5} [/tex]9.) [tex] \frac{83 \times 7 + 3}{7} = \frac{584}{7} \\ \frac{79 \times 7 + 4}{7} = \frac{557}{7} \\ \frac{584}{7} - \frac{557}{7} = \frac{27}{7} = 3 \frac{6}{7} [/tex]