M is thrice as good as workman as N and together they finish a piece of work in 30 days. In how many days will M alone finish the work?
1). 50
2). 40
3). 60
4). 45
Let the work done by M in 1 day be y of the total work
Since M is thrice as good as N
⇒ Work done by N in 1 day be y/3 of the total work
According to the problem statement
⇒ 30(y + y/3) = 1
⇒ 4y/3 = 1/30
⇒ y = 1/40
This shows that the M can do the whole work in 40 days alone
∴ Number of days required by M to work alone are 40 days