Working together, A & B finish a DTP work in 10 days. Had A worked at half his efficiency and B at 5 times her efficiency, then they would have finished the DTP work in half the scheduled time. In how many days can B complete the DTP work on her own?
Option (e)
Let us solve this using answer options
It is better to start with option (d) or option (e) as it is given that B takes 15th the actual time in the second case. Option (d) and (e) are multiples of 5
Solving for option (d)
1x+115=110⇒ A takes 30 days
They would have finished the work in half the time if A takes 60 days and B takes 3 days
But ,160+13≠15. Hence, this is not the answer
Solving for option (e)
1x+130=110⇒ A takes 15 days
They would have finished the work in 5 days, if A takes 30 days and B takes 6 days
130+16=15. Hence, this is the answer.