[klaus52]

d)
x + y = 450        |    y=2,6 * x
x + 2,6 * x = 450
3,6 * x = 450
x= 450 / 3,6 = 125

y= 2,6*125 = 325



e)
x + y = 450

0,5x = 1/3 y <=> y = 1,5 x

x + 1,5x = 450 <=> x= 450 / 2,5 = 180

y= 1,5*180 = 270