-
A can do a piece of work in 18 days and B in 12 days. They began the work together, but B left the work 3 days before its completion. In how many days, in all, was the work completed?
-
- 12 days
- 10 days
- 9.6 days
- 9 days
Correct Option: D
Let the work be finished in x days.
According to the question, A worked for x days while B worked for (x – 3) days
| ∴ | + | = 1 | ||
| 18 | 12 |
| ⇒ | = 1 | |
| 36 |
⇒ 5x – 9 = 36
↠ 5x = 45
| ⇒ x = | = 9 | |
| 5 |
Hence, the work was completed in 9 days.
Aliter :
Using Rule 8,
Here, x = 18, y = 12, m = 3
| Total time taken = |  |  | x | |
| x + y |
| = | | | × 18 = 9 days | |
| 18 + 12 |
