# Military Flight Aptitude Test: Basic Algebra

Before taking the Military Flight Aptitude Test, one subject area you should review is basic algebra. *Algebra* is a fun subject in which letters represent variables, and your role is to find out exactly what that variable stands for.

The most common algebraic variable is *x, *which is why you often hear the phrase “solve for *x*” in reference to unknown quantities. But you can use any variable you like as long as the same variable represents only one quantity throughout a given problem.

Algebra deals in *equations,* or statements that two given quantities are equal. 16 + 17 = 33 is an equation. In algebra, equations include variables that you have to solve for. Here’s an example problem: Three fuel tankers, each carrying 2,000 gallons of jet fuel, completely empty their loads to fill up an empty tank. How much fuel total is in the tank?

Let *T* stand for the fuel in the tank and *F* stand for the fuel in one tanker. You can use these variables to create an algebra formula of *T* = 3*F* for this problem. You know that *F* = 2,000 gallons, so you can substitute that into the equation to get *T* = 3 x 2,000 gallons, or *T* = 6,000 gallons.

The four arithmetic operations (addition, subtraction, multiplication, and division) are all possible in algebra. You can express each operation through algebra equations as follows:

The sum (addition) of two numbers

*x*and*y*is written as*x*+*y.*The difference (subtraction) between two numbers

*x*and*y*is written as*x*–*y.*The product (multiplication) of two numbers

*x*and*y*is written as*xy*or*x*x*y.*The quotient (division) of two numbers

*x*and*y*is written as*x*/*y*or*x*÷*y.*

You can perform any calculation on either side of an equation as long as you do it to both sides of the equation.