SAT Math: When to Plug-in Numbers II (w/ examples)

Previously, we talked about the strategy of plugging in a number whenever an SAT Math question mentions a number or integer. This number plug-in strategy works equally as well for questions with equations in the answer choices – questions that are often among the hardest on the entire SAT Math section.

Whenever you see an SAT Math question with equations in the answer choices, plug in a number.

Pick a number and plug it into the question to get a value. Then plug the number into each answer choice to see which one produces the same value.

Remember:
When plugging in numbers, be sure to pick EASY numbers and ALWAYS plug in for ALL answer choices.

Example 1:

The number plug-in strategy also works great for word problems with equations in the answer choices.

Example 2:

Answers and explanations in the comments.

From my SAT guide SAT Unlocked, which includes a complete list of practice questions in The Official SAT Study Guide for which this number plug-in strategy is effective.

SAT Math: When to Plug-in Numbers (w/ example)

Plugging in numbers is a simple and very effective strategy that can help you answer many SAT Math questions, including even some of the hardest ‘Numbers and Operations’ questions.

Any time a question mentions a ‘number’ or ‘integer’, make up your own value that fits the description in the question, and then plug that value into the answer choices to see which one works.

A couple of things to remember:

Use EASY numbers.
1 (sometimes), 2, 3, 4, 5, 10, and 100 are usually best, depending on the question.

Check ALL answers
Occasionally, the number you plug in may be correct for more than one answer choice (especially if you plug in ’1′). Be sure to check all answers to make sure only one is correct. If you get more than one correct answer, plug in a different number for the remaining choices.

Example:

Answer and explanation in the Comments.

From my SAT course book SAT Unlocked, which includes a complete list of questions in The Official SAT Study Guide for which this number plug-in strategy is effective.