x1:x2 = 3:5 - > x1 = 0.6*x2
x2:x3 = 7:8 -> x2 = 0.875*x3
x1+x2+x3 = 72
0.6(0.875*x3) + 0.875*x3 + x3 = 72
2.4x3 = 72
x3 = 30
x2 = 26.25
x1 = 15.75
x1:x2 = 3:5 - > x1 = 0.6*x2
x2:x3 = 7:8 -> x2 = 0.875*x3
x1+x2+x3 = 72
0.6(0.875*x3) + 0.875*x3 + x3 = 72
2.4x3 = 72
x3 = 30
x2 = 26.25
x1 = 15.75