Ratios
A ratio compares two quantities by division. For example, if there are 3 red balls and 5 blue balls, the ratio of red balls to blue balls is 3:5.
Percentages
A percentage expresses a part of a whole as a fraction of 100. For example, if 30 out of 100 students pass a test, the percentage of students passing is 30%.
Fractions
A fraction represents a part of a whole. For example, 1/2 represents one half of something.
Decimals
Decimals are another way of expressing parts of a whole. For example, 0.5 is the decimal form of one half.
Scientific Notation
Scientific notation is a way of expressing very large or very small numbers in a concise form. It consists of a number between 1 and 10 multiplied by a power of 10.
For example, the speed of light in meters per second is approximately 299,792,458. In scientific notation, this is written as 2.99792458 x 10^8.
Other Forms
There are many other ways of expressing numbers, such as square roots, logarithms, and so on. Each has its own use and application.