A ratio is a comparison of the sizes of two or more quantites of the same kind by division.
If a and b are two quantities of the same kind (in same units),then the fraction is called the ratio of a to b. Thus the ratio of a to b=
. It is written as
.
The quantites a and b are called the terms of the ratio, a is called the first term(or antecedent) and b is called the second term(or consequent).