Let Sunny invested for T months. Ratio of profit share of Dinesh and Sunny =
12000×12
9000×T
=
16
T
Let profit share of Dinesh and Sunny be Rs 16x and Rs Tx respectively. ATQ 16x+Tx = 8000 And Tx = 1600 So, 16x = 6400 x = 400 T = 4 Sunny invested for 4 months ∴ after 8 months sunny joined the business.