Question

1) -1/4 * (4*(-5/7)) =
2) (-4/5) * 2/3 * (-5/4) =
3) 2 1/3 * (-7/9) * 9/7 =
4) (-8/9) * 2 4/17 * (-9/8) =

помогите пжш((((((,,

Answer 1

$-\frac{1}{4} *(4*(-\frac{5}{7} ))=-\frac{1}{4} *(-\frac{20}{7}) =\frac{5}{7} \\\\(-\frac{4}{5} )*\frac{2}{3} *(-\frac{5}{4} )=(-\frac{4}{5} )*(-\frac{5}{4} )*\frac{2}{3} =\frac{2}{3} \\\\2\frac{1}{3} *(-\frac{7}{9} )*\frac{9}{7} =\frac{7}{3} *(-\frac{7}{9} )*\frac{9}{7} =\frac{7}{3} *-1=-\frac{7}{3} =-2\frac{1}{3} \\\\(-\frac{8}{9} )*2\frac{4}{17} *(-\frac{9}{8} )=\frac{38}{17} *(-\frac{8}{9} )*(-\frac{9}{8} )=\frac{38}{17} =2\frac{4}{17}$