Решение примеров на сложение дробей

a) $$\frac{3}{4} + \frac{2}{3} = \frac{3 \cdot 3}{4 \cdot 3} + \frac{2 \cdot 4}{3 \cdot 4} = \frac{9}{12} + \frac{8}{12} = \frac{9+8}{12} = \frac{17}{12}$$

б) $$\frac{3}{10} + \frac{2}{15} = \frac{3 \cdot 3}{10 \cdot 3} + \frac{2 \cdot 2}{15 \cdot 2} = \frac{9}{30} + \frac{4}{30} = \frac{9+4}{30} = \frac{13}{30}$$

в) $$\frac{4}{9} + \frac{1}{6} = \frac{4 \cdot 2}{9 \cdot 2} + \frac{1 \cdot 3}{6 \cdot 3} = \frac{8}{18} + \frac{3}{18} = \frac{8+3}{18} = \frac{11}{18}$$

г) $$\frac{7}{15} + \frac{3}{40} = \frac{7 \cdot 8}{15 \cdot 8} + \frac{3 \cdot 3}{40 \cdot 3} = \frac{56}{120} + \frac{9}{120} = \frac{56+9}{120} = \frac{65}{120} = \frac{13 \cdot 5}{24 \cdot 5} = \frac{13}{24}$$