问题 解答题
已知 
a
2
=
b
3
=
c
4
,求 
3a+b-2c
c-b+a
的 值.
答案

设设

a
2
=
b
3
=
c
4
=d,则a=2d,b=3d,c=4d,

3a+b-2c
c-b+a

=

3×2d+3d-2×4d
4d-3d+2d

=

9d-8d
3d

=

d
3d

=

1
3

答:

3a+b-2c
c-b+a
的值是
1
3

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