<p>Yes. Let’s start with a simple Level 1 problem with a block:</p>
<p>If 3(a+b)-4=41, then a+b=</p>
<p>The block in this problem is a+b. </p>
<p>The most common error in this problem is to apply the distributive property to the left hand side of the equation 3(a+b)-4=41 to get 3a+3b-4=41. This would make the question more difficult. If you are always looking out for blocks, you will never make this mistake.</p>
<p>Note that this question has the same solution as the following question:</p>
<p>If 3x-4=41, then x=</p>
<p>In other words, we can substitute the block for a single variable, and we get an equivalent problem.</p>