А) 
[tex]4 \frac{2}{3} + 5 \frac{4}{7} = \frac{14}{3} + \frac{39}{7} = \frac{98}{21}+ \frac{117}{21} = \frac{215}{21} = 10 \frac{5}{21} " alt="2\frac{1}{5}+3 \frac{2}{3} = \frac{11}{5} + \frac{11}{3} = \frac{33}{15}+ \frac{55}{15} = \frac{88}{15}= 5 \frac{5}{15} = 5 \frac{1}{3} [tex] \\\\ б) [tex]4 \frac{2}{3} + 5 \frac{4}{7} = \frac{14}{3} + \frac{39}{7} = \frac{98}{21}+ \frac{117}{21} = \frac{215}{21} = 10 \frac{5}{21} " align="absmiddle" class="latex-formula">
