Q:

**?A and B together can do a piece of work in 18 days, B and C in 24 days, and A and C in 36 days. The number of days, all of them working together take to complete the work, is-?**

- ?18?
- ?16?
- ?17?
- ?15?
- 23

**Level:**

?

$\frac12$

Q:

**?A and B together can do a piece of work in 18 days, B and C in 24 days, and A and C in 36 days. The number of days, all of them working together take to complete the work, is-?**

- ?18?
- ?16?
- ?17?
- ?15?
- 23

?

$\frac12$