A can do a piece of work in 90 days & Y can do it in 80 days. They began working together but A leaves after some days and then B completed the remaining work in 46 days. The number of days after which A left the work was?
Choose the correct option: A) 12 days B) 18 days C) 16 days D) 19 days E) 21 days

Rationale: a and b did the work for some days . after that , b completed the remaining work in 46 days . in 46 days , word done by b = 1 80 x 46 = 23 45 remaining work = 1 – 23 / 45 = 17 / 45 remaining work is done by both a and b together = 17 / 45 x 90 x 80 / 90 + 80 = 16 days c
Answer: C