(1)1/X + 1/Y = 1/10
(2)1/Y + 1/Z = 1/122
(3)4/X + 12/Y + 4/Z = 1
(3)=4(1/x+2/y+1/y+1/z)=1
(4)=(1)+(2)=1/x+2/y+1/z=11/60
(3)=4(11/60)+4/y=1 y=15
x=30 z=60
(1)1/X + 1/Y = 1/10
(2)1/Y + 1/Z = 1/122
(3)4/X + 12/Y + 4/Z = 1
(3)=4(1/x+2/y+1/y+1/z)=1
(4)=(1)+(2)=1/x+2/y+1/z=11/60
(3)=4(11/60)+4/y=1 y=15
x=30 z=60