Multiple-choice Math Strategies
The SAT five-choice multiple-choice questions test areas including arithmetic, algebra, geometry, data interpretation, etc. None of the problems require the use of a calculator, but you may find it helpful in doing basic arithmetic computations, square roots, and percentages and in comparing and converting fractions. Remember to practice using the calculator you plan to take to the test if you can't handle it very fast.
Before answering each question, ask yourself: What does the question ask? and What do I know? Then make sure to:
- Answer the question asked.
- Check if your answer makes sense.
- Check your answer again using a different method, if possible.
Don't jump on the calculator for everything. You should know when to use the calculator. If you do not know how to solve a problem, neither does your calculator. The most important thing is to set up your work on paper first, and then plug the info into your calculator.
Substitute number for variables (indicated by letters such as x, y and z). It's always easier to work with numbers than with letters. For example:
If x - 4 is 2 greater than y, then x + 5 is how much greater than y?
(A) 1
(B) 3
(C) 7
(D) 9
(E) 11
Choose any value for x. Say x = 4. Then 4 - 4 = 0, and 0 is 2 greater than y. So y = -2. If x = x, then x + 5 = 4 + 5 = 9, and so x + 5 is 11 more than y. Therefore, the correct answer is choice (E).
Here are the rules:
- Use common sense when picking numbers to substitute.
- Substitute numbers that are easy to work with.
- Make sure you check the special cases: 0, 1, at least one number between 0 and 1, a number or numbers greater than 1, and a few negative numbers.
Plug in the answer choices. Sometimes you can find the correct by working backwards. Try plugging in the answer choices to see which one works. When plugging in the answer choices, start with choice (C). If the choices are numbers, they are usually listed in order from the lowest to highest value, or the vice versa. If (C) turns out to be too high, you don't need to try out the larger numbers. If (C) is too low, you can forget the smaller numbers. For example:
If a rectangle has sides of 2x and 3x and an area of 24, what is the value of x?
(A) 2
(B) 3
(C) 4
(D) 5
(E) 6
Get started by testing (C), and assume that x = 4. Then the sides would have lengths 2(4) = 8 and 3(4) = 12 and the rectangle would have an area of 8 X 12 = 96. Since 96 is larger than 24, start working with smaller answer choices. You can instantly forget about (D) and (E). You have saved time!
If you come across a question that asks for an irregular shape, don't worry! The question actually asks for the difference between the areas of two or more regular shapes. Take a look at the figure below.
The shaded area is the difference of areas between the rectangular and the two inside circles. Thinking so, you immediately find the problem so easy to solve.
Your eye is a good estimator. Figures are always drawn to scale unless you see a warning. So use your eye as an estimator if you need to.
Finally, and once again, don't forget using your guessing and eliminating skills if needed. Remember that the questions are arranged from easy to hard. Pace yourself and don't spend too much time on any one question. Don't worry if you are still slow at the math questions. Your math problem-solving skills can be considerably improved through practicing at this Web site. So can your problem-solving speed.
If you want to start practicing now, click here to login "SAT Practice" section. We suggest that you come back to this page and read the content again after you have spent 2 weeks of practicing. You will definitely have a better understanding about the strategies!
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