<p>In the Blue Book, Practice Test #2, Math Section #6 on page 476...question 18...I have absolutely no idea how to solve this question.</p>
<p>There is a diagram of 5 different looking boxes. For purposes of posting this online, I'll call the boxes A, B, C, D, E.</p>
<p>The question is: If the 5 letters shown above are placed in a row so that C is never at either end, how many different arrangements are possible?</p>
<p>The answer is 72.</p>
<p>What is the quickest, easiest, most efficient way to do this? It's the last question in the section too, so the fastest method would be the most helpful.</p>