9. Ram, Sachin and Ravi start a business with an investment of ₹ 1500 each. Ram remains in partnership for 6 months, Sachin for 8 months and Ravi for 12 months. Then, find the ratio of their profits.
a) \( 3: 2: 4 \)
b) \( 3: 4: 6 \)
c) \( 5: 2: 1 \)
d) \( 4: 2: 3 \)
e) None of these