№2 1. 2/5 + 1/5 2. 7/8 - 3/8 3. 1/3 + 1/6 4. 3/4 × 2/9 5. 5/6 : 2/3

№2

• 1. \[ \frac{2}{5} + \frac{1}{5} = \frac{3}{5} \]
• 2. \[ \frac{7}{8} - \frac{3}{8} = \frac{4}{8} = \frac{1}{2} \]
• 3. \[ \frac{1}{3} + \frac{1}{6} = \frac{2}{6} + \frac{1}{6} = \frac{3}{6} = \frac{1}{2} \]
• 4. \[ \frac{3}{4} \times \frac{2}{9} = \frac{3 \times 2}{4 \times 9} = \frac{6}{36} = \frac{1}{6} \]
• 5. \[ \frac{5}{6} : \frac{2}{3} = \frac{5}{6} \times \frac{3}{2} = \frac{5 \times 3}{6 \times 2} = \frac{15}{12} = \frac{5}{4} = 1\frac{1}{4} \]