Виконай дії:
Розв'язок:
1) $3\frac{2}{5} + \left(-4\frac{1}{3}\right) - 2\frac{7}{15} =$
$= 3\frac{2}{5} + \left(-4\frac{1}{3}\right) + \left(-2\frac{7}{15}\right) =$
$= 3\frac{2}{5} + \left(-6\frac{5+7}{15}\right) = 3\frac{2}{5} + \left(-6\frac{12}{15}\right) =$
$= 3\frac{2}{5} + \left(-6\frac{4}{5}\right) =$
$= -\left(6\frac{4}{5} - 3\frac{2}{5}\right) = -3\frac{2}{5}$;
2) $2\frac{5}{24} - 4\frac{5}{8} - \left(-3\frac{5}{12}\right) + \left(-\frac{1}{6}\right) =$
$= 2\frac{5}{24} + \left(-4\frac{5}{8}\right) + 3\frac{5}{12} + \left(-\frac{1}{6}\right) =$
$= 5\frac{5+10}{24} + \left(-4\frac{15+4}{24}\right) =$
$= 5\frac{15}{24} + \left(-4\frac{19}{24}\right) = 4\frac{39}{24} + \left(-4\frac{19}{24}\right) =$
$= \frac{20}{24} = \frac{5}{6}$;
3) $-2\frac{1}{4} + 3{,}7 - 2{,}9 - \left(-3\frac{2}{5}\right) =$
$= -2{,}25 + 3{,}7 + (-2{,}9) + 3{,}4 =$
$= 7{,}1 + (-5{,}15) = 1{,}95$;
4) $4{,}9 - 7\frac{3}{10} - 8\frac{3}{4} - (-8{,}2) =$
$= 4{,}9 + (-7{,}3) + (-8{,}75) + 8{,}2 =$
$= 13{,}1 + (-16{,}05) = -2{,}95$.