问题 填空题
已知
a
b
=
c
d
=
e
f
=
2
3
,则
a+e
b+f
=______.
答案

a
b
=
c
d
=
e
f
=
2
3

∴a=

2
3
b,e=
2
3
f,

a+e
b+f
=
2
3
b+
2
3
f
b+f
=
2
3
(b+f)
b+f
=
2
3

故答案为

2
3

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