a,b,c不等於0 4/ab=6/bc=3/ca,則(a+b+c):(a+b-c)=?

x:y:z=4:1:6
x=4r
y=r
z=6r
a+b+c:a+b-c=4r+r+6r:4r+r-6r
=11:-1

4/ab=6/bc=3/ca
4abc/ab=6abc/bc=3abc/ca
4c=6a=3b
a:b:c=12:24:18
設a+b+c=54
a=12 b=24 c=18
(a+b+c):(a+b-c)
=(12+24+18):(12+24-18)
=3:1

Sol
4/(ab)=6/(bc)=3/(ca)
4abc/(ab)=6abc/(bc)=3abc/(ca)
4c=6a=3b
[4，6，3]=2[2，3，3]=2*2*3=12
4c=6a=3b=12p<>0
a=2p，b=4p，c=3p
(a+b+c)：(a+b－c)
=(2p+4p+3p)：(2p+4p－3p)
=9p：3p
=3：1