A company contracts to paint 3 houses

A company contracts to paint 3 houses. Mr.Brown can paint a house in 6 days while Mr.Black would take 8 days and Mr.Blue 12 days. After 8 days Mr.Brown goes on vacation and Mr. Black begins to work for a period of 6 days. How many days will it take Mr.Blue to complete the contract?

AQuA-RAT — Algebra Question Answering with Rationales (Ling et al., DeepMind, 2017) · test #55