Вычислим: 6\frac{1}{2}⋅7\frac{5}{8}-(2\frac{3}{4})^2.
1) $$6\frac{1}{2} \cdot 7\frac{5}{8} = \frac{13}{2} \cdot \frac{61}{8} = \frac{13 \cdot 61}{2 \cdot 8} = \frac{793}{16} = 49\frac{9}{16}$$.2) $$(2\frac{3}{4})^2 = (\frac{11}{4})^2 = \frac{11^2}{4^2} = \frac{121}{16} = 7\frac{9}{16}$$.3) $$49\frac{9}{16} - 7\frac{9}{16} = 42$$.Ответ: 42