Question

помогите пожалуйста​

Answer 1

$1)\; \; 1\frac{3}{4}=\frac{7}{4}\; \; ,\; \; \frac{4}{7}\; \; ,\; \; 1\frac{1}{2}=\frac{3}{2}\\\\\frac{7}{4}\; \; i\; \; \frac{4}{7}\; \; vzaimno\; obratnue\; chisla\\\\2)\; \; \Big (\frac{11}{12}\cdot \frac{12}{11}\Big )\cdot \Big (\frac{13}{14}\cdot \frac{14}{13}\Big )\cdot \frac{15}{16}=1\cdot 1\cdot \frac{15}{16}=\frac{15}{16}\\\\\star \; \; a\cdot \frac{1}{a}=1\; \; \star$

$3)\; \; P=\frac{1}{3}+1\frac{3}{10}+2\frac{1}{6}=\frac{1}{3}+\frac{13}{10}+\frac{13}{6}=\frac{20+78+130}{60}=\frac{228}{60}=3\frac{4}{5}=3,8$