x+2/3 = y-1/5 = z+1/4 = k
x+2/3 = k
x = 3k-2
y-1/5 = k
y = 5k+1
z+1/4 = k
z = 4k-1
x+y+z = 142
3k-2 +5k+1 + 4k-1 = 142
12k = 142+2-1+1
12k = 144
k = 144:12
k = 12
x = 3k-2
x = 3*12-2
x = 36-2
x = 34
y = 5k+1
y = 5*12+1
y = 60+1
y = 61
z = 4k-1
z = 4*12-1
z = 48-1
z = 47
V: 34+61+47 = 95+47 = 142