Some carpenters promised to do a job in 9 days but 5 of them were absent and remaining men did the job in 12 days. The original number of carpenters was:
Answer & explanation
Correct answer: option 2
Let there were originally x number of carpenter .
Total work = efficiency × number of days
Total work = 9 × x = 9x
5 went on leave . So leftover carpenter does the work in 12 days
total work by them = 12(x - 5)
As per questions,
9x = 12(x - 5)
9x = 12x - 60
9x - 12x = 60
-3x = -60
x = 20 is number of carpenters