A carpenter worked alone for 1 day on a job that would take him 6 more days to finish. He and another carpenter completed the job in 6 more days. How many days would it have taken the second carpenter to do the complete job working alone?
Pick:  A) 4 2/3  B) 7  C) 9  D) 24  E) 21
A carpenter worked only 1 day on something that takes him 6 MORE days.   Means;   Carpenter finishes his work in 7 days.   Let his buddy finish the same task in x days.   Respective rates per day:   1/7 AND 1/x   To complete 1 work:   First guy worked for 5 days @ rate=1/7 per day.   Second one worked for 6 days @ rate=1/x per day   Expression:   Days*Rate=Work   5*1/7+6*1/x=1   5x+42=7x   2x=42   x=21 days.   Ans:21
<result>E</result>
A carpenter worked alone for 1 day on a job that would take him 6 more days to finish. He and another carpenter completed the job in 6 more days. How many days would it have taken the second carpenter to do the complete job working alone?