Subject: mathqa
Question: a starts business with rs . 3500 and after 5 months , b joins with a as his partner . after a year , the profit is divided in the ratio 2 : 3 . what is b ' s contribution in the capital ?
Option: 
A: rs . 9120
B: rs . 9228
C: rs . 9129
D: rs . 9000
Answer: D