David and ANDREW can finish the work 12 days if they work together. They worked together for 8 days and then ANDREW left. David finished the remaining work in another 8 days. In how many days David alone can finish the work? Pick:
A) 30 days B) 60 days C) 70 days D) 80 days E) 24 days

Rationale: amount of work done by david and andrew in 1 day = 1 / 12 amount of work done by david and andrew in 8 days = 8 ã — ( 1 / 12 ) = 2 / 3 remaining work â € “ 1 â € “ 2 / 3 = 1 / 3 david completes 1 / 3 work in 8 days amount of work david can do in 1 day = ( 1 / 3 ) / 8 = 1 / 24 = > david can complete the work in 24 days answer : e
Answer: E