Rohan and Mohit together can build a wall in 8 days
So, one day work by Rohan and Mohit
= Mohit and Vikas together can build a wall in 10 days
So, one day work by Mohit and Vikas
= Vikas and Rohan together can build a wall in 12 days
So, one day work by Vikas and Rohan
= All the three complete the same wall together in one day
They work all together in
= days