An outlet pipe can empty 2/3 of a cistern in 16 minutes. In 4 minutes, what part of the cistern will be emptied?  Choose the correct answer.
A) 1/2 B) 1/3 C) 1/4 D) 1/6 E) 1/8
4/16 * 2/3 = 1/6   The answer is 1/6.
<result>D</result>
An outlet pipe can empty 2/3 of a cistern in 16 minutes. In 4 minutes, what part of the cistern will be emptied?