саша = x;лена = y;наташа=z;
x+y+z=8 z=8-(x+y) z=8- 5, 4/25 z= 2 ,21/25
x+y=5 ,4/25 x=8-(y+z) x=8 - 5, 11/20 x=2 ,9/20
y+z=5 ,11/20 y=5, 11/20 - z y= 5, 11/20 - 2 21/25 y=2 ,71/100
саша = x;лена = y;наташа=z;
x+y+z=8 z=8-(x+y) z=8- 5, 4/25 z= 2 ,21/25
x+y=5 ,4/25 x=8-(y+z) x=8 - 5, 11/20 x=2 ,9/20
y+z=5 ,11/20 y=5, 11/20 - z y= 5, 11/20 - 2 21/25 y=2 ,71/100