Ответ:
а) \(2,4+1\frac{2}{3}=\frac{12}{5}+\frac{5}{3}=\frac{36+25}{15}=\frac{61}{15}=4\frac{1}{15}\).
б) \(3,7-2\frac{2}{5}=3\frac{7}{10}-2\frac{4}{10}=1\frac{3}{10}=1,3\).
в) \(7\frac{1}{6}-6,2=7\frac{1}{6}-6\frac{1}{5}=\frac{43}{6}-\frac{31}{5}=\frac{215-186}{30}=\frac{29}{30}\).
г) \(9\frac{4}{15}-1,8=9\frac{4}{15}-1\frac{4}{5}=9\frac{4}{15}-1\frac{12}{15}=8\frac{7}{15}\).
Ответ: а) \(4\frac{1}{15}\); б) \(1,3\); в) \(\frac{29}{30}\); г) \(8\frac{7}{15}\).
