<p><span style="color:#27ae60;"><span style="font-size:20px;">Solving the Problem</span></span></p>
<p>This is a <span style="color:#8e44ad;"><strong>Words to Algebra</strong></span> problem, so we can convert from words to algebraic expressions as we read:</p>
<blockquote>
<p>A third-grade teacher has n boxes, each containing 12 pencils.</p>
</blockquote>
<p>Total Pencils = $12n$</p>
<blockquote>
<p>After the teacher gives p pencils to each student in the class, the teacher has t pencils left over.</p>
</blockquote>
<ul>
<li>$t = Total Pencils - (p * number of students)$</li>
<li>$s = number of students$</li>
<li>$t = 12n - ps$</li>
</ul>
<blockquote>
<p>Which of the following represents the number of students in the class?</p>
</blockquote>
<p>We can just re-arrange the equation to show what $s$ (number of students) will equal:</p>
<ul>
<li>$t = 12n - ps$</li>
<li>$t + ps = 12n$</li>
<li>$ps = 12n - t$</li>
<li>$s = \frac{12n-t}{p}$</li>
</ul>
<p>So, the correct answer should be <span style="color:#27ae60;">A</span>.</p>