A cardinal number tells "how many." Cardinal numbers are also known as "counting numbers," because they show quantity. Here are some examples using cardinal numbers:8 puppies14 friends Ordinal…
The factorial of a number is the product of all the whole numbers, except zero, that are less than or equal to that number. For example, to find the factorial of 7 you would multiply together all…
A rounded number has about the same value as the number you start with, but it is less exact. For example, 341 rounded to the nearest hundred is 300. That is because 341 is closer in value to 300…
Cube V = a3, in which a is the length of one of the sides.Rectangular Prism V = abc, in which a is the length, b is the width, and c is the depth.Sphere V = (4πr3)/3, in which π is about 3.1416 and…
Perimeter The perimeter of a geometrical figure is the complete distance around that figure. To find the perimeter, simply add up the lengths of the figure's sides. Example: What is the perimeter…
A triangle has three sides and is made of straight lines. A triangle may be classified by how many of its sides are of equal length. Or, it may be classified by what kind of angles it has.
Types of…
Even numbers are numbers that can be divided evenly by 2. Even numbers can be shown as a set like this:{ … -4, -2, 0, 2, 4, … } Odd numbers are numbers that cannot be divided evenly by 2. Odd…
Learn the difference between rational and irrational numbers, and watch a video about ratios and rates
Rational Numbers
A rational number is a number that can be written as a ratio. That means it…
The number known as pi (π) has fascinated people for millenia. The digits to the right of its decimal point can keep going forever, and there is absolutely no pattern to these digits. A team of…
Integers include positive whole numbers, negative whole numbers, and zero.
The “set of all integers” is often shown like this:
Integers = {… -5, -4, -3, -2, -1, 0, 1, 2, 3, 4, 5, …}
The dots at…
