А) 3/5 + 5/16 б) 2/7 + 5/28 в) 4/7 + 3/14 г) 7/100 + 3/10

А) $\frac{3}{5 } + \frac{5}{16} = \frac{3*5}{5*16} + \frac{5*5}{16*5} = \frac{48}{80} + \frac{25}{80} = \frac{73}{80}$

б) $\frac{2}{7} + \frac{5}{28} = \frac{2*4}{7*4} + \frac{5}{28}= \frac{8}{28} + \frac{5}{28}= \frac{13}{28}$

в) $\frac{4}{7} + \frac{3}{14} = \frac{4*2}{7*2} + \frac{3}{14} = \frac{8}{14} + \frac{3}{14} = \frac{11}{14}$

г) $\frac{7}{100} + \frac{3}{10} = \frac{3*10}{10*10} = \frac{7}{100} + \frac{30}{100} = \frac{37}{100}$