Question

已知：2分之a等于3分之b，a≠0，b≠0，a-b分之a+b的值是

A.5 B.-5 C.1 D.-1

Answer 1

2分之a等于3分之b
∴a=2b/3

(a+b)/(a-b)=(2b/3 +b)/(2b/3-b)=(5b/3)/(-b/3)=-5

选B

Answer 2

选B
∵2分之a=3分之b
a=3分之2b
∴原式=(2b/3 +b)/(2b/3-b)
=(5b/3)/(-b/3)
=-5
∴选B