(b) By options, the number of workers = 3
Then, time taken by them to finish the job when one worker is with drawn each day = 3
Then, time taken by them working together =
x 3 = 2 days
So, 3 workers can do the work in 2 days.
∴ Work done by 3 workers in 1 day =
Work done by 1 worker in 1 day =
= Now, by given condition when one worker is with drawn
+
+
= 1
= 1 ⇒
= 1
1 = 1, hence there were 3 workers