Difference Between Rate and Ratio

In the world of Physics and the world in general, both rate and ratio are very important tools used to understand various quantifiable quantities that are present in nature.

With the help of these mathematical tools, we can understand how various things happen and how they operate around us. The terms rate and ratio are mainly used in physics, mathematics, finance, business, etc.

Both of these terms are very simple to understand. Still, since they used the same mathematical function, that is, division, to be calculated, it is understandable that there might be some confusion between these two terms.

Key Takeaways

1. The Rate compares two quantities measured in different units, while Ratio compares two quantities measured in the same units.
2. Rate is often used to express speed, distance, or time, while Ratio is commonly used to compare the sizes of two or more objects or quantities.
3. While Rate is expressed as a fraction or decimal, Ratio is expressed as a simplified fraction or a colon (:).

Rate vs. Ratio

A rate measures the amount of change in one quantity concerning another quantity,  measured over time. A ratio is a comparison of two or more quantities with the same measurement units. It is expressed as a fraction or a colon. Ratios can also be expressed as decimals or percentages.

Rate is the amount a quantity changes concerning one or more other quantities. One is usually familiar with the term rate of change of a quantity concerning another quantity.

The ratio tells us about the relationship of how quantity varies when another quantity varies at the same time. However, it is important to note that both the quantities used in a ratio belong to the same unit.

Comparison Table

Parameters of Comparison	Rate	Ratio
Definition	Rate defines the amount of change of one quantity concerning another.	The ratio tells us about the relationship between two quantities.
Dimension	The rate has a dimension of one or more.	The ratio is dimensionless.
Dependency	Usually, the numerator is dependent on the denominator.	Usually, both are mutually dependent.
Use	Rate is mostly used in science and finance.	The ratio is mostly used in science and mathematics.
Variation	The numerator usually varies, while the denominator has a unit value.	The numerator and the denominator change if either alters the value.

What is Rate?

Rate is the amount a quantity changes concerning one or more other quantities. One is usually familiar with the term rate of change of a quantity concerning another quantity.

So basically, the reading tells us how often or how frequently the value of a single quantity changes while the other quantities stay fixed at a certain value. Usually, the quantity of the denominator is equal to one, so any change in the numerator can be easily analyzed or calculated.

The most common forms of rate which we use in our day-to-day life include speed, acceleration, price of vegetables, etc. When we say that a car is moving at a hundred kilometers per hour (100 km/hour), we mean to say that the car covers a distance of hundred kilometers every single hour.

This is an example of a rate showing the distance change concerning time. Another example is the price of vegetables. Suppose we say that a dozen bananas cost 30 rupees.

This is an example of a rate because, for every dozen bananas, the price is 30 rupees. One very important feature to note about rate is that rate will always have one or more dimensions.

This is because the units in the numerator and denominator denote different quantities; hence and division, they do not cancel each other out, which is why the final quantity, which is created by the date, has some dimension.

What is Ratio?

The ratio tells us about the relationship of how quantity varies when another quantity varies at the same time. However, it is important to note that both the quantities used in a ratio belong to the same unit.

While studying in school, people are most familiar with the term ratio used in mathematics, and the definition of this term remains the same across all subjects.

Ratios are used in various subjects for various purposes, whether in mathematics to calculate the circumference of a circle or in science to calculate the molarity of a solution or anywhere else.

It is important to note that, in a ratio, the numerator or the denominator need not necessarily be a unit quantity. However, the numerator and denominator should be reduced as much as possible. This means there should be no common factor between the denominator and numerator.

The ratio was also useful for analyzing demographics. One of the most common ratios used as a demographic tool is the sex ratio of a country. The sex ratio tells us about the number of women in a country per thousand men.

In special cases like these, where the numerator or the denominator is specified, one need not reduce these terms to the lowest possible value. The values in a ratio follow a proportion, and if one increases, the other increases proportionately.

Similarly, if one decreases, the other decreases proportionately too.

Main Differences Between Rate and Ratio

1. The main difference between rate and ratio is that rate shows the amount of change a quantity undergoes concerning another quantity. In contrast, ratio tells us how two quantities are related quantitatively.
2. The rate has a dimension of one or more than one, while the ratio is dimensionless.
3. In rate, often the numerator depends on the denominator, while in ratio, both the numerator and the denominator are mutually dependent.
4. Rate is mostly used for science and finance, while the ratio is mostly for science and mathematics.
5. In rate, the numerator usually varies while the denominator has a unit value, while in ratio, both values vary simultaneously.

References

1. https://link.springer.com/article/10.1023/A:1022318321416
2. https://journals.sagepub.com/doi/abs/10.1177/0956797615617799