• commonly a ratio is the comparison of two values of the same kind,
which may be written as a to b, a:b or as a fraction a/b.
• a part-part ratio compares a number of parts of a whole
to other parts in the whole.
•
a part-whole ratio compares a number of parts of a whole
to the total of all parts in the whole.
• a ratio may have more than two terms.