A waiter's salary consists of his salary and tips. During one week his tips were 3/4 of his salary. What fraction of his income came from tips ?
Choose the correct choice from the following answers.
A) 3 / 7	B) 5 / 4	C) 5 / 8	D) 5 / 9	E) 6 / 9

Rationale: "income = salary ( s ) + tips = s + s * 3 / 4 = s * 7 / 4 tips = s * 3 / 4 fraction of his income came from tips = ( s * 3 / 4 ) / ( s * 7 / 4 ) = 3 / 7 answer : a"
Answer: A