<p>For questions where they might ask for the 80th term in a sequence, is there a formula that I can use?</p>
<p>Tn=T1(r^(n-1))</p>
<p>where Tn represents the nth term and T1 is the first term. r is a ratio raised to the n-1 power. And the parentheses means you multiply r^(n-1) by T1.</p>
<p>They don't generally ask questions that require you know this formula. That's why they call it the SAT Reasoning Test, not the SAT Calculation Test. For example, if you look at the sequence, you might realize the answer has to be an even number, and only one of their choices is even.</p>
<p>You could go ahead and calculate, and get the answer. But usually you're better off if you can reason your way to the answer.</p>