若a:b=2:3,b:c=1:2,且a+b+c=66,则a=_.

问题描述:

若a:b=2:3,b:c=1:2,且a+b+c=66,则a=______.

a:b=2:3,
b:c=1:2=(1×3):(2×3)=3:6,
a:b:c=2:3:6,
66×

2
2+3+6
=12.
故答案为:12.