A ratio describes a multiplicative comparison between two quantities, indicating how many units of one quantity correspond to a given number of units of the other; it may be written in words, with a colon, or as a fraction, and its order determines the comparison. The interpretation distinguishes part-to-part from part-to-whole comparisons and avoids treating a ratio as a difference, establishing a foundation for equivalent ratios, rates, proportions, and percent.
A ratio compares quantities by telling how many of one quantity correspond to another. The order matters.
For example, suppose a basket has 6 apples and 4 oranges.
Suppose the question asks for the ratio of apples to oranges.
Write apples first and oranges second:
This can also be written as:
The ratio means:
For every apples, there are oranges.
This is a part-to-part comparison because it compares one part of the basket with another part.
It does not mean there are more apples. A ratio describes how the amounts compare, not their difference.
The ratio of oranges to apples is:
This means:
For every oranges, there are apples.
It is different from because the quantities are in the opposite order.
There are pieces of fruit altogether. The ratio of apples to all the fruit is:
This is a part-to-whole comparison because apples are compared with the total number of fruits.
When interpreting any ratio:
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