If x/y = 7/3, then (x + y)/(x - y) = ?
Options
A) 5  B) 5 / 2  C) - 1 / 6  D) - 1 / 5  E) - 5

Rationale: "any x and y satisfying x / y = 7 / 3 should give the same value for ( x + y ) / ( x - y ) . say x = 7 and y = 3 , then ( x + y ) / ( x - y ) = ( 7 + 3 ) / ( 7 - 3 ) = 5 / 2 . answer : b ."
Answer: B