Parents and Teachers: Support Ducksters by following us on Ducksters Facebook or Ducksters Twitter.
Ducksters Educational SiteDucksters Educational Site
History Biography Geography Science Games

Advertisement

Kids Math

Inequalities

In most math problems you are trying to find the exact answer. We use the equal sign "=" to say that two things are the same. However, sometimes we just want to show that something is bigger or smaller than something else. Or maybe we just want to say that two things are not equal. These cases are called inequalities.

Special Signs

There are special signs used with inequalities to indicate which side is bigger, which side is smaller, or that the two sides aren't equal.

Here are the five major inequality signs:

<

>


less than
less than or equal to
greater than
greater than or equal to
not equal


Greater Than or Less Than

When you want to say that one thing is bigger than another, you use the greater than or less than signs. You put the wide part of the sign towards the greater side and the small part, or point, towards the smaller side.

Examples:

8 > 3
4 < 9
0 < 12

You could also use variables like this:

a + b < 17
22 > y
(x + y) x 8 < z

If you need to remember which way the greater than or less than sign should point, you can remember it this way. Think of the sign as an alligator's mouth. The alligator wants to eat the larger side. Like this:



Adding in an Equal Sign

When we want to say something is greater than or equal to something else, we add in an equal sign. This symbol looks like this: . As you can see it's sort of a combination of the > sign plus the = sign.

We use the opposite type of sign when we want to indicate less than or equal to, like this: .

Example Problems:

1) The number X could be 3 or any number greater than 3. You could write this as:

X ≥ 3

2) The number Y could be 2 or any number less than 2. You could write this as:

Y ≤ 2

3) Billy had 6 candy bars. Amy ate some of his candy bars. How many candy bars does Billy have now?

# candy bars < 6

4) Jacob had 11 math problems for homework. We know he got 4 problems correct, but we don't know the results of the other problems. How many did Jacob get correct?

# answers correct ≥ 4

Multiple Inequalities

Sometimes you can use more than of these signs in the same expression in order to indicate a range. For example, if you had between 3 and 9 apples you would write:

3 < apples < 9

If you had at least 12 marbles and as many has 20 marbles:

12 ≤ marbles ≤ 20



Kids Math Subjects

Multiplication
Intro to Multiplication
Long Multiplication
Multiplication Tips and Tricks
Square and Square Root

Division
Intro to Division
Long Division
Division Tips and Tricks

Fractions
Intro to Fractions
Equivalent Fractions
Simplifying and Reducing Fractions
Adding and Subtracting Fractions
Multiplying and Dividing Fractions

Decimals
Decimals Place Value
Adding and Subtracting Decimals
Multiplying and Dividing Decimals

Misc
Basic Laws of Math
Inequalities
Rounding Numbers
Significant Digits and Figures
Prime Numbers
Roman Numerals
Binary Numbers
Statistics
Mean, Median, Mode, and Range
Picture Graphs

Algebra
Exponents
Linear Equations - Introduction
Linear Equations - Slope Forms
Order of Operations
Ratios
Ratios, Fractions, and Percentages
Solving Algebra Equations with Addition and Subtraction
Solving Algebra Equations with Multiplication and Division

Geometry
Circle
Polygons
Quadrilaterals
Triangles
Pythagorean Theorem
Perimeter
Slope
Surface Area
Volume of a Box or Cube
Volume and Surface Area of a Sphere
Volume and Surface Area of a Cylinder
Volume and Surface Area of a Cone


Back to Kids Math

Back to Kids Study






About Ducksters Privacy Policy   

Follow us on Ducksters Facebook or Ducksters Twitter

This site is a product of TSI (Technological Solutions, Inc.), Copyright 2017, All Rights Reserved. By using this site you agree to the Terms of Use.