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Basic Math & Pre-Algebra

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Find a Starting Amount from a Final Amount

Some math word problems give you the amount that you end up with and ask you to find out how much you started with. These problems can be difficult if you’re not used to thinking backwards. Here’s an example [more…]

How to Convert Metric Units of Measurement

If you want to convert from English to metric units or from metric to English units, there is a simple way to do this that uses only one formula for each type of conversion. [more…]

How to Recognize a Polyhedron

A polyhedron is the three-dimensional equivalent of a polygon, which is a shape that has only straight sides. Similarly, a polyhedron is a solid that has only straight edges and flat faces [more…]

How to Measure in Three Dimensions

Measuring in three dimensions is similar to measuring in two dimensions; however, in 3-D, the boundary of a solid is called its surface area (not its perimeter) [more…]

Compare Numbers Using a Bar Graph

A bar graph gives you an easy way to compare numbers or values. For example, the following figure shows a bar graph comparing the performance of five trainers at a fitness center. [more…]

Use a Pie Chart to Find Percentages and Amounts

A pie chart, which looks like a divided circle, shows you how a whole object is cut up into parts. Pie charts are most often used to represent percentages. For example, the following figure is a pie chart [more…]

Plot Numbers Using a Line Graph

The most common use of a line graph is to plot how numbers change over time. For example, the following figure is a line graph showing last year’s sales figures for Tami’s Interiors. [more…]

Plot Cartesian Coordinate Points on a Cartesian Graph

When math folks talk about using a graph, they’re usually referring to a Cartesian graph (also called the Cartesian coordinate system). The below figure shows an example of a Cartesian graph. [more…]

How to Solve Problems with a Cartesian Graph

You can use a Cartesian graph to solve certain types of math problems. When you draw two lines that represent different parts of a word problem, the point at which the lines intersect [more…]

How to Solve a Geometry Word Problem

In order to solve a geometry word problem, you need to read the problem carefully, recognize shapes in the drawing, pay attention to labels, and use whatever formulas you have to help you answer the question [more…]

How to Determine Probable Outcomes with Coins and Dice

Although the basic probability formula isn’t difficult, sometimes finding the numbers to plug into it can be tricky. One source of confusion is in counting the number of outcomes, both favorable and possible [more…]

How to Draw Lines on a Cartesian Graph

By plotting points on a Cartesian graph, you can draw lines between these points and use them to show mathematical relationships. The following examples focus on the number of dollars that two people, [more…]

How to Use the Metric System

The metric system provides units of measurement for distance, volume, mass, time, and temperature. It builds these units using a basic unit and a set of [more…]

How to Subtract Mixed Numbers

Whether mixed numbers have the same denominators or different denominators, subtracting them is a lot like subtracting whole numbers: you stack them up one on top of the other, draw a line, and subtract [more…]

How to Multiply Two Fractions and Reduce the Answer

To multiply two fractions, you need to have a basic knowledge of the multiplication table and the ability to reduce the answer to its lowest terms. [more…]

Common Fraction and Decimal Equivalents in Business Math

Fractions and decimals form the basis of much of the math in business. The following table shows you some of the more commonly used fractions and their decimal equivalents. An ellipsis [more…]

Common Area and Perimeter Formulas

You may need to find out the size of an office space, perimeters of buildings, and tracts of land for your business. Keep these frequently used formulas handy for your business math needs: [more…]

Important Angle Measures in Degrees

When you’re figuring out things like lot lines or fencing for your business, you’re working with angles. These figures are the more commonly used angle measures and can help you estimate angles for your [more…]

Applying Algebraic Formulas and Equivalences in Word Problems

When it comes to math, don't let the idea of solving word problems overwhelm you. If you prepare and have the right attitude, you can approach word problems confidently. One way to prepare is to have the [more…]

Figuring Simple and Compound Interest in Math Word Problems

When you're working on money-type mathematical word problems, financial formulas come in handy. The following formulas are for simple and compound interest. [more…]

Formulas for Perimeter, Area, Surface Area, and Volume

You'll find geometric figures showing up frequently in word problems. Geometric figures have names, classifications, and characteristics and are measured in two or more ways. Study this list of the formulas [more…]

Math Word Problems For Dummies Cheat Sheet

If the thought of working math word problems frightens you, don't panic. Arm yourself with the following algebraic, geometric, and financial formulas before you start so you're ready to dive in and solve [more…]

How to Tell One Differential Equation from Another

Before you can solve a differential equation, you need to know what kind it is. There are several different types of equations, including linear, separable, exact, homogeneous, and nonhomogeneous. [more…]

Two Effective Ways to Solve Differential Equations

You can solve a differential equation in a number of ways. The two most effective techniques you can use are the method of undetermined coefficients and the power series method. [more…]

Solving Differential Equations Using Laplace Transform Solutions

Laplace transforms are a type of integral transform that are great for making unruly differential equations more manageable. Simply take the Laplace transform of the differential equation in question, [more…]


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