A and B started a business with initial investments in the ratio 6 : 3, after some months B withdrawn his investment, and their share in the annual profits were in the ratio 8 : 7. Then how long B was in the business ?	Choose the correct choice from the following options
A) 6 months	B) 8 months	C) 21 months	D) 5 months	E) 7 months
Let Sumit in the business for ‘a’ months.   Investment Ratio Amit to Sumith = 6 : 3.   Profit sharing ratio = 8 : 7.   Amit is in the business for 12 months.   Then Sumit in the business for   (6× 12) / (3 × a) = 8 / 7 =&gt; 24a = 504 or   a = 504 / 24= 
<gadget id="calculator">504 / 24</gadget>
<output>21</output>
21 or 21 months   Option 21 months
<result>C</result>
A and B started a business with initial investments in the ratio 6 : 3, after some months B withdrawn his investment, and their share in the annual profits were in the ratio 8 : 7. Then how long B was in the business ?