A waitress's income consists of her salary and tips.During one week ,her tips were 3/4 of her salary.What fraction of her income for the week came from tips?	Select the correct option:
A) 1 / 9
B) 1 / 6
C) 3 / 7
D) 4 / 9
E) 5 / 9

Rationale: "her tips were 3 / 4 of her salary . let ' s say her salary = $ 4 this mean her tips = ( 3 / 4 ) ( $ 4 ) = $ 3 so , her total income = $ 4 + $ 3 = $ 7 what fraction of her income for the week came from tips $ 3 / $ 7 = 3 / 7 = c"
Answer: C