Problem 5

$$\begin{array}{lcl} 5.\:It \:takes\:3\:friends\:28\:minutes\:to\:wash\:all\:the\:windows\:in\\ Blair's\:apartment.\:How \:long \:would\:it\:take\:6\:friends,\\ working\:at\:the\:same\:rate,\:to\:wash\:all\:the\:windows\:?\\ \\ (A)\:16\:minutes\\ \\ (B)\:14\:minutes\\ \\ (C)\:22\:minutes\\ \\ (D)\:10\:minutes\\ \\ (E)\:8\:minutes\\ \end{array}$$