00 08 12/ لے حب 912 25 = 8 18-4 43 +8 ②45+6=54-10-231-5일 ④2+3= ⑤ 6+3= =⑥125+13= ④7+35= 232 +5,018 - 5TH 400 8 7 56 د 56 911 56 00 릴리라붸⑧ TeachTouch P >

Решим примеры, записанные на интерактивной доске.

1) $$3\frac{1}{8}+2\frac{1}{4}=3\frac{1}{8}+2\frac{2}{8}=5\frac{3}{8}$$

2) $$7\frac{5}{7}+6\frac{3}{5}=\frac{54}{7}+\frac{33}{5}=\frac{54 \cdot 5}{7 \cdot 5}+\frac{33 \cdot 7}{5 \cdot 7}=\frac{270}{35}+\frac{231}{35}=\frac{501}{35}=14\frac{11}{35}$$

3) $$9\frac{1}{8}+7\frac{1}{7}=\frac{73}{8}+\frac{50}{7}=\frac{73 \cdot 7}{8 \cdot 7}+\frac{50 \cdot 8}{7 \cdot 8}=\frac{511}{56}+\frac{400}{56}=\frac{911}{56}=16\frac{15}{56}$$

4) $$2\frac{1}{2}+3\frac{1}{4}=\frac{5}{2}+ \frac{13}{4}=\frac{5 \cdot 2}{2 \cdot 2}+\frac{13}{4}=\frac{10}{4}+\frac{13}{4}=\frac{23}{4}=5\frac{3}{4}$$

5) $$6\frac{1}{6}+3\frac{1}{3}=\frac{37}{6}+\frac{10}{3}=\frac{37}{6}+\frac{10 \cdot 2}{3 \cdot 2}=\frac{37}{6}+\frac{20}{6}=\frac{57}{6}=9\frac{3}{6}=9\frac{1}{2}$$

6) $$12\frac{1}{9}+13\frac{1}{7}=\frac{109}{9}+\frac{92}{7}=\frac{109 \cdot 7}{9 \cdot 7}+\frac{92 \cdot 9}{7 \cdot 9}=\frac{763}{63}+\frac{828}{63}=\frac{1591}{63}=25 \frac{16}{63}$$

7) $$7\frac{7}{8}+3\frac{5}{9}=\frac{63}{8}+\frac{32}{9}=\frac{63 \cdot 9}{8 \cdot 9}+\frac{32 \cdot 8}{9 \cdot 8}=\frac{567}{72}+\frac{256}{72}=\frac{823}{72}=11\frac{31}{72}$$

8) $$11\frac{1}{4}+12\frac{1}{12}=\frac{45}{4}+\frac{145}{12}=\frac{45 \cdot 3}{4 \cdot 3}+\frac{145}{12}=\frac{135}{12}+\frac{145}{12}=\frac{280}{12}=23\frac{4}{12}=23\frac{1}{3}$$

Ответ: смотри выше