A pipe can empty 2/3rd of a cistern in 12mins. In 5 mins, what part of the cistern will be empty? Choose the correct choice:
A) 2 / 3 B) 5 / 18 C) 4 / 9 D) 3 / 8 E) 4 / 7

Rationale: 2 / 3 - - - - 12 ? - - - - - 5 = = > 5 / 18 b
Answer: B