Hi people please help me with this maths problem...

mark opens a company with R40 000 capital and 6 months later Tom joins mark with R80 000 capital. Jerry decides to join the two another 6 months later with R80 000 capital
how should the profit be split amoung the three after 3 years from when mark opened the company.

please take the R infront of the digits as dollar or pound for people that are oversease
as i am using my own currency