Question

How are ratios and percent-ages related?

Questions in McDougal Littell Science "Cells and Heredity" text book

Answer 1

A "ratio" is any numerical comparison of two values. A "percentage" is a ratio that is "normalized" to equivalent parts per hundred.

Explanation:

The percentage normalization allows the easier comparisons of different ratios. For example, the raw data "ratios" of men to women in Alaska and Arkansas might be `231650/153049` and `5392039/5809328`.

Those numbers may be accurate, but they are hard to work with. If we are really interested in the relative difference in populations between those States, we would make each ratio a percentage by multiplying the resulting decimal from the fraction (ratio) by 100.

`231650/153049 xx 100 = 151%`
and `5392039/5809328 xx 100 = 92.8%`.

NOW we can easily see that there are 51% more men than women in Alaska, while in Arkansas it is closer to equal - actually 7.2% more women (100 - 92.8).

So, ratios and percentages can be derived from the same comparisons, but are used for different reasons to make better use of the information.