Thirty men take 20 days to complete a job working 9 hours a day. How many hour a day should 40 men work to complete the job? (a) 8 hrs (b) 7 1/2 hrs (c) 7 hrs (d) 9 hrs (e) none of these options
Answer is option (e)
Explanation:
?30 * 20 * 9 = 5400 man-hours required to complete the job
:
Let x = no. hrs a day to do the same job (assuming in 20 days)
40 * 20 * x = 5400
800x = 5400
x = 5400/800
x = 6.75 hrs a day for 20 days to do the same job