3. Вычисли: а) 3 5/18 : 59/60 + 2,6; б) (2 12/13 − 1 9/52) · (1,4 + 3,8).

а) \(3\frac{5}{18}:\frac{59}{60}+2,6=\frac{59}{18}\cdot\frac{60}{59}+\frac{13}{5}=\frac{10}{3}+\frac{13}{5}=\frac{89}{15}=5\frac{14}{15}\).

б) \(\left(2\frac{12}{13}-1\frac{9}{52}\right)\cdot(1,4+3,8)=\left(\frac{152}{52}-\frac{61}{52}\right)\cdot5,2=\frac{91}{52}\cdot\frac{26}{5}=\frac{7}{4}\cdot\frac{26}{5}=\frac{91}{10}=9\frac{1}{10}\).

Ответ: а) \(5\frac{14}{15}\); б) \(9\frac{1}{10}\).