Задание 2. Найдите значение выражения: 1) (17/10 − 1/20) · 2/15; 2) (5/22 − 8/11) · 11/5; 3) (5/26 − 3/25) · 13/2; 4) (10/13 + 15/4) · 26/5; 5) (17/26 + 11/13) · 17/6; 6) (11/12 + 11/20) · 15/8; 7) (3/4 − 1/6) · 3; 8) (2/5 + 13/15) · 6; 9) (3/8 − 1/20) · 10; 10) (2/20 + 7/30) · 15; 11) (9/10 − 7/15) · 3; 12) (1/6 + 1/4) · 9.

1) \(\left(\frac{17}{10}-\frac{1}{20}\right)\cdot\frac{2}{15}=\frac{33}{20}\cdot\frac{2}{15}=\frac{11}{50}\).

2) \(\left(\frac{5}{22}-\frac{8}{11}\right)\cdot\frac{11}{5}=\left(\frac{5}{22}-\frac{16}{22}\right)\cdot\frac{11}{5}=-\frac{1}{2}\cdot\frac{11}{5}=-\frac{11}{10}\).

3) \(\left(\frac{5}{26}-\frac{3}{25}\right)\cdot\frac{13}{2}=\frac{47}{650}\cdot\frac{13}{2}=\frac{611}{1300}\).

4) \(\left(\frac{10}{13}+\frac{15}{4}\right)\cdot\frac{26}{5}=\frac{235}{52}\cdot\frac{26}{5}=\frac{47}{2}\).

5) \(\left(\frac{17}{26}+\frac{11}{13}\right)\cdot\frac{17}{6}=\frac{3}{2}\cdot\frac{17}{6}=\frac{17}{4}\).

6) \(\left(\frac{11}{12}+\frac{11}{20}\right)\cdot\frac{15}{8}=\frac{22}{15}\cdot\frac{15}{8}=\frac{11}{4}\).

7) \(\left(\frac{3}{4}-\frac{1}{6}\right)\cdot3=\frac{7}{12}\cdot3=\frac{7}{4}\).

8) \(\left(\frac{2}{5}+\frac{13}{15}\right)\cdot6=\frac{19}{15}\cdot6=\frac{38}{5}\).

9) \(\left(\frac{3}{8}-\frac{1}{20}\right)\cdot10=\frac{13}{40}\cdot10=\frac{13}{4}\).

10) \(\left(\frac{2}{20}+\frac{7}{30}\right)\cdot15=\frac{1}{3}\cdot15=5\).

11) \(\left(\frac{9}{10}-\frac{7}{15}\right)\cdot3=\frac{13}{30}\cdot3=\frac{13}{10}\).

12) \(\left(\frac{1}{6}+\frac{1}{4}\right)\cdot9=\frac{5}{12}\cdot9=\frac{15}{4}\).

Ответ: 1) 11/50; 2) −11/10; 3) 611/1300; 4) 47/2; 5) 17/4; 6) 11/4; 7) 7/4; 8) 38/5; 9) 13/4; 10) 5; 11) 13/10; 12) 15/4.