问题 填空题
如果
a
b
=
c
d
=
e
f
=
5
7
,那么
a+c+2e
b+d+2f
=______.
答案

a
b
=
c
d
=
e
f
=
5
7

∴a=

5
7
b,c=
5
7
d,2e=
10
7
f,

a+c+2e
b+d+2f
=
5
7
b+
5
7
d+
10
7
f
b+d+2f
=
5
7
(b+d+2f)
b+d+2f
=
5
7

故答案为:

5
7

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