如果x/2=y/3=z/4不等于0,那么x+y+z/x+y-z的值是 A.7 B.8 C.9 D.10

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如果x/2=y/3=z/4不等于0,那么x+y+z/x+y-z的值是 A.7 B.8 C.9 D.10

x/2=y/3=z/4 设x=2a,y=3a,z=4a
则x+y+z/x+y-z =( 2a+3a+4a )/ ( 2a+3a-4a) = 9
选C

设x/2=y/3=z/4=k，则 x=2k,y=3k z=4k
所求式=2k+3k+4k/2k+3k-4k
=9k/k
=9