Correct Answer - Option 1 : 9 days
Given:
A and B together can do a piece of work in 6 days
A alone do the whole work in 18 days
Concept used:
M and N can do a piece of work in x days
M can alone do the work in y days
where, y > x
The number of days in which N can complete the work = xy/(y - x)
Calculation:
A and B together can do a piece of work in 6 days
A alone can do the whole work in 18 days
The number of days in which B can complete the work = xy/(y - x)
The number of days in which B can complete the work = (18 × 6)/(18 - 6)
⇒ 108/12 = 9 days
∴ The number of days required for B to finish the work is 9 days.
