Students who struggled to learn mathematical formulas in high school will be relieved to learn that it's not necessary to memorize these formulas for the GED test. Instead, you'll be given a formula page providing all necessary formulas in your test booklet. Knowing the formulas, however, is much different from knowing how to use them, so you'll still need to brush up on basic math. Moreover, memorizing the formulas can help save you time because you won't be constantly flipping to the formulas sheet.
You'll have to know how to find the area, perimeter and volume of basic geometric shapes such as squares, rectangles, cubes and trapezoids. You'll also need to be able to measure the circumference of a circle. The formulas will help you solve these problems as long as you understand basic geometric terminology. You'll need to understand, for example, that the radius of a circle is a measure of the edge of the circle to its center; otherwise, the formulas won't be very helpful.
You'll be tested on lots of basic arithmetic, including measuring the mean and median of a group of numbers and calculating interest. You'll receive the formulas for these problems, but because you're being tested on number operations, you'll need to have good arithmetic skills. You'll also need to know how to eliminate unnecessary information in word problems. For example, if you're told that over two days, the scores on a test were 100, 90 and 70, you'll need to know that the information about time is irrelevant to finding the mean and median.
You'll need to be able to read visual representations of data such as pie charts and bar graphs. You'll also have to be able to plot coordinates on a graph. You won't be given a formula for doing this; instead, you'll need to know where the X and Y axes are located on a graph and how to glean information from a visual aid.
Basic algebra, including the use of variables in formulas, plays a critical role in the GED test, and you'll need to understand how to fill in variables to solve almost any problem that uses a formula. You'll also, however, be tested on the quadratic equation. You'll receive a formula, but you will need to know how to apply it and how to deduce information from the answer.