<PRE><B>Question 897788</B>
It is unclear if we are starting with 60 or 61 (60 plus 1 contractor) workers
It is unclear if we are continuing  with 70, 71 (70 plus 1 contractor),
 130 (60 +70) or 131 (60+70+1) workers

60 workers
60*60=3600 man days
60*16=960
3600-960=2640 man days to finish the job
2640/70=37.71 days
2640/71=37.18 days
2640/130=20.31 days
2640/131=20.15 days

61 workers
60*61=3660 man days
61*16=976
3660-976=2684 man days to finish the job

2684/70=37.80 days
2684/71=37.18 days
2684/130=20.66 days
2684/131=20.148 days
</PRE>