There is a work which can be completed by A with 12 days and B by 18 days. A and B works together for 3 days and B left. After that how many days for A to complete the work?
Answers:
A) 4 B) 5 C) 6 D) 7 E) 8
work done by A per day=1/12   work done by B per day=1/18   work done by A and B per day=1/12+1/18=5/36   work done by A and B for 3 days=5*3/36=5/12   work remasining=1-5/12=7/12   . After that A takes 7days to complete the work   ANSWER:7
<result>D</result>
There is a work which can be completed by A with 12 days and B by 18 days. A and B works together for 3 days and B left. After that how many days for A to complete the work?