a) x+y+z=24
x/3=y/4=z/5
x=3k
y=4k
z=5k
3k+4k+5k=24
12k=24
k=24:12
k=2
x=3×2
x=6
y=4×2
y=8
z=5×2
z=10
b) x+y+z=36
x/3=y/4=z/5
x=3k
y=4k
z=5k
3k+4k+5k=36
12k=36
k=36:12
k=3
a=3×3
a=9
b=4×3
b=12
c=5×3
c=15
c) x+y+z=132
x/3=y/4=z/5
x=3k
y=4k
z=5k
3k+4k+5k=132
12k=132
k=132:12
k=11
a=3×11
a=33
b=4×11
b=44
c=5×11
c=55