2.383 Найдите произведение: a) $$3\frac{1}{9} \cdot 5$$; б) $$8\frac{2}{9} \cdot 4$$; в) $$4 \cdot 2\frac{1}{5}$$; г) $$8 \cdot 2\frac{1}{11}$$; д) $$5\frac{1}{5} \cdot 5$$; e) $$3\frac{3}{7} \cdot 7$$; ж) $$6 \cdot 10\frac{1}{6}$$; з) $$11\frac{1}{3} \cdot 3$$; и) $$23\frac{5}{8} \cdot 8$$; к) $$11\frac{7}{15} \cdot 15$$.

Решение:

1. a) $$3\frac{1}{9} \cdot 5 = \frac{28}{9} \cdot 5 = \frac{28 \cdot 5}{9} = \frac{140}{9} = 15\frac{5}{9}$$
2. б) $$8\frac{2}{9} \cdot 4 = \frac{74}{9} \cdot 4 = \frac{74 \cdot 4}{9} = \frac{296}{9} = 32\frac{8}{9}$$
3. в) $$4 \cdot 2\frac{1}{5} = 4 \cdot \frac{11}{5} = \frac{4 \cdot 11}{5} = \frac{44}{5} = 8\frac{4}{5}$$
4. г) $$8 \cdot 2\frac{1}{11} = 8 \cdot \frac{23}{11} = \frac{8 \cdot 23}{11} = \frac{184}{11} = 16\frac{8}{11}$$
5. д) $$5\frac{1}{5} \cdot 5 = \frac{26}{5} \cdot 5 = \frac{26 \cdot 5}{5} = 26$$
6. e) $$3\frac{3}{7} \cdot 7 = \frac{24}{7} \cdot 7 = \frac{24 \cdot 7}{7} = 24$$
7. ж) $$6 \cdot 10\frac{1}{6} = 6 \cdot \frac{61}{6} = \frac{6 \cdot 61}{6} = 61$$
8. з) $$11\frac{1}{3} \cdot 3 = \frac{34}{3} \cdot 3 = \frac{34 \cdot 3}{3} = 34$$
9. и) $$23\frac{5}{8} \cdot 8 = \frac{189}{8} \cdot 8 = \frac{189 \cdot 8}{8} = 189$$
10. к) $$11\frac{7}{15} \cdot 15 = \frac{172}{15} \cdot 15 = \frac{172 \cdot 15}{15} = 172$$

Ответ:

1. a) $$15\frac{5}{9}$$
2. б) $$32\frac{8}{9}$$
3. в) $$8\frac{4}{5}$$
4. г) $$16\frac{8}{11}$$
5. д) $$26$$
6. e) $$24$$
7. ж) $$61$$
8. з) $$34$$
9. и) $$189$$
10. к) $$172$$