Найдите значение выражения: a) $$(2\frac{1}{4}+1\frac{5}{6})\cdot (4-3\frac{38}{49})$$;

a) $$(2\frac{1}{4}+1\frac{5}{6})\cdot (4-3\frac{38}{49})$$

1) $$2\frac{1}{4}+1\frac{5}{6}=2\frac{3}{12}+1\frac{10}{12}=3\frac{13}{12}=4\frac{1}{12}=\frac{49}{12}$$;

2) $$4-3\frac{38}{49}=3\frac{49}{49}-3\frac{38}{49}=\frac{11}{49}$$;

3) $$\frac{49}{12}\cdot \frac{11}{49}=\frac{11}{12}$$.

Ответ: $$\frac{11}{12}$$