SAT Tip of the Week: Solve for the Right Variable
Welcome to the second installment in AJ Tutoring’s SAT Tip of the Week series! This week, we’ll be focusing on a common trick the SAT test-makers like to play in the math section.
To do well on the SAT math section, yes, you must know the content — you need to have a good grasp of basic arithmetic, number properties, algebra, and geometry. But if you spend some time looking at the hardest SAT math questions, you’ll notice pretty quickly that the content of the math questions doesn’t really get more difficult than that. You’re not solving matrices or differentiating equations. Rather, you’re working through more complex questions with multiple steps, using higher-order logic, and reading carefully.
One trick that pops up on the most difficult SAT math questions has to do with the wording of the question. Math questions will often set up a relatively simple equation, which you can solve for “x” without too much trouble. However, the question might ask you for the value of 3x. If you didn’t read the question carefully, you might overlook this detail and choose the wrong answer.
Here’s a sample problem that illustrates this, taken from the College Board’s Official SAT Study Guide:
It’s easy enough to translate the wording of the question into an equation: 4w=w+4. Solving for w, you should get w=4/3. Many students stop there, believing that because they solved the equation and got an answer listed in the answer choices (answer choice C). they’ve gotten the problem right. Of course, the SAT test-makers anticipated that students would solve for w, and built that answer choice into the problem.
But not so fast! Take 5 seconds to re-read what the question is asking you to solve for. In this case, we’re looking for the value of 3w. The value of 3w is 4, which is the correct answer (answer choice E).
The takeaway: Before you choose a final answer to an SAT math question, take some time to reread what the question is asking you to find. Make sure you’ve solved for the correct variable!