Raju can do a piece of work in 10 days wiki in 12 days and Tinku in 15 days they all start the work together but Raju leaves after 2 days and vicky leaves 3 days before the work is completed in how many days is the work completed ?

Assume Total work to be LCM(10,12,15) == 60 units.
R completes 60/10days== 6units per day
V completes 60/12== 5units per day
T completes 60/ 15== 4units per day
In first two days all together worked
2*( 6+5+4 ) units== 30 units completed in 2days
Remaining 30 units left
Suppose N more days are taken to complete this remaining work
V works N-3 days and T works N days
(N-3)*5units + N* 4units== 30 units
N== 5days.
Hence, total time == 5+ initial 2days== 7days

let total work is 60a. so one day work of raju(6a) wiki(5a), tinki(4a).
solve it to get answer. 7 days

Answer is 7 days.

7 days

Ans-6