jane and ashley take 13 1 / 3 days and 40 days respectively to complete a project when they work on it alone . they thought if they worked on the project together , they would take fewer days to complete it . during the period that they were working together , jane took an 8 day leave from work . this led to jane ' s working for 4 extra days on her own to complete the project . how long did it take to finish the project ?  Options:
A) 10 days  B) 15 days  C) 16 days  D) 17 days  E) 20 days

Rationale: let us assume that the work is laying 40 bricks . jane = 3 bricks per day ashley = 1 brick per day together = 4 bricks per day let ' s say first 8 days ashley works alone , no of bricks = 8 last 4 days jane works alone , no . of bricks = 12 remaining bricks = 40 - 20 = 20 so together , they would take 20 / 4 = 5 total no . of days = 8 + 4 + 5 = 17 answer is d
Answer: D