Question 327363
In 4 days the painter completes the whole work W.
In 1 day the painter completes 1/4 work.
In 1 day the apprentice completes 1/6 work.
Let the number of days taken to complete the work by them be n days.
Hence nW/6 + (n - 1)W/4 = W
=> n/6 + (n - 1)/4 = 1
=> 2n + 3n - 3 = 12
=> 5n = 15
=> n = 3
Hence the work is completed in 3 days.