A started a business with an investment of Rs.5000. After 4 months, B joined the business with an investment of Rs.4000. After 2 more months, C joined them with an investment of Rs.y. At the end of the year, the ratio of the profit share of A, B and C is 15:8:12 respectively. Find the value of y?
A. 8000
B. 4500
C. 6600
D. 7200
E. None of these
Sol:
(5000 * 12 + 4000 * 8)/(y * 6) = (15 + 8)/12
(60000 + 32000)/6y = 23/12
6y = 92000 * 12/23
y = 48000/6
y = 8000