1. Найдите значение выражения: a) |9,8|+|-0,8|; 6) |-5\frac{3}{14}|-|-3\frac{8}{21}|; в) |-1\frac{3}{17}|\cdot |2\frac{4}{15}|; г) |-2\frac{3}{8}|:|1\frac{1}{4}|-|-2\frac{2}{19}|.

Решение:

a) |9,8|+|-0,8| = 9,8 + 0,8 = 10,6

б) |-5$$\frac{3}{14}$$|-|-3$$\frac{8}{21}$$| = 5$$\frac{3}{14}$$ - 3$$\frac{8}{21}$$ = $$\frac{73}{14}$$ - $$\frac{71}{21}$$ = $$\frac{73 \cdot 3 - 71 \cdot 2}{42}$$ = $$\frac{219 - 142}{42}$$ = $$\frac{77}{42}$$ = $$\frac{11}{6}$$ = 1$$\frac{5}{6}$$

в) |-1$$\frac{3}{17}$$|$$\cdot$$|2$$\frac{4}{15}$$| = 1$$\frac{3}{17} \cdot 2\frac{4}{15}$$ = $$\frac{20}{17} \cdot \frac{34}{15}$$ = $$\frac{4}{1} \cdot \frac{2}{3}$$ = $$\frac{8}{3}$$ = 2$$\frac{2}{3}$$

г) |-2$$\frac{3}{8}$$|:|1$$\frac{1}{4}$$|-|-2$$\frac{2}{19}$$| = 2$$\frac{3}{8}$$ : 1$$\frac{1}{4}$$ - 2$$\frac{2}{19}$$ = $$\frac{19}{8} : \frac{5}{4} - \frac{40}{19}$$ = $$\frac{19}{8} \cdot \frac{4}{5} - \frac{40}{19}$$ = $$\frac{19}{2} \cdot \frac{1}{5} - \frac{40}{19}$$ = $$\frac{19}{10} - \frac{40}{19}$$ = $$\frac{19 \cdot 19 - 40 \cdot 10}{190}$$ = $$\frac{361 - 400}{190}$$ = -$$\frac{39}{190}$$

Ответ: a) 10,6; б) 1$$\frac{5}{6}$$; в) 2$$\frac{2}{3}$$; г) -$$\frac{39}{190}$$