Enter the values

#### Formula for calculating proportions

A : B = C : D

## Free Proportion Calculator Online – Solve Fractions in Minutes

A proportion is an equal relationship between two numbers, amounts, or groups. When two numbers are in proportion, they are related by a certain factor. This factor is usually represented by a fraction, which can be written as two numbers separated by a colon. For example, if we say that *A : B = 2 : 3*, the ratio of A to B is 2 to 3.

## Basic Proportion

In mathematics, a proportion is a statement that two ratios are equal. A particular type of equation involves two fractions with the same denominator.

## Cross Multiplication

Cross multiplication is a method that you can use to solve proportion equations. It is a way of multiplying the numerators and denominators of the fractions in the equation to cancel out the fractions and solve for the unknown.

## How to Set Up a Proportion Equation

- Identify the values as what is known and what is unknown.
- Write an equation using a ratio of the known values.
- Solve the equation to find the value of the unknown.

## Types of Proportions

There are three types of proportions: direct, inverse, and joint.

**Direct Proportion**Direct proportion occurs when two variables are directly proportional to each other. For example, if we say that

*price : quantity = 10 : 5*, this means that for every 10 units of price, there will be 5 units of quantity. In other words, as the price increases, the quantity also increases.**Inverse Proportion**Inverse proportion occurs when two variables are inversely proportional to each other. For example, if we say that

*speed : distance = 2 : 1*, this means that for every 2 units of speed, there will be 1 unit of distance. In other words, as the speed increases, the distance decreases.**Joint Proportion**Joint proportion occurs when two or more variables are jointly proportional. For example, if we say that

*A : B = C : D*, the ratio of*A*to*B*equals the ratio of*C*to*D*. In other words, as the value of one variable increases, the values of the other variables also increase. Note: You can write*A : B = C : D as A/B = C/D**A : B :: C : D as (B x C) = (A x D)*

## How to Use the Proportion Calculator?

To use our proportion calculator, enter the known or unknown values into the respective fields. The calculator will then automatically calculate the proportion for you.

### Finding Missing Values in a Proportion

If you have a proportions calculator, you can use it to find missing values.

For instance, the ratio of men to women is 2 to 3, and you want to find the number of women given that there are 100 men, you would set up the proportion like this:

*100/2 = x/3*

To solve for x, you would multiply both sides by 3. It gives you the following:

*3(100/2) = 3x/3*

*300/2 = x*

*150 = x*

*There are 150 women.*

You can use this method to find any missing value in a proportion as long as you know at least two other values.

### Comparing Two Proportions

To compare two proportions, you can use the proportion calculator. This tool allows you to input each group's proportion and then calculate the difference between the two proportions. For example, let's say you want to compare the proportion of men and women who have a college degree. You would first input the proportion of men with a college degree and then the proportion of women with a college degree. The calculator would then give you the difference between the two proportions.

### Finding the Percent of Change

To find the percent of change, we need to use proportion. We set up a proportion using the original value and the new value. Then, we solve for the percent change.

Let’s say that we want to find the percent of change from 10 to 15. We would set up the proportion like this:

*10/100 = 15/x*

Then, we would solve for x. We do this by cross-multiplying. It gives us the following:

*1000 = 15x*

To solve for x, we divide both sides by 15. It gives us the following:

*1000/15 = x*

Thus:

*x = 66.66%*

It is the percent of change from 10 to 15.

### Solving Markup and Markdown Problems

You want to buy a new pair of shoes that are on sale for 30% off. The original price of the shoes is $100. What is the sale price of the shoes? To solve this problem, we can use proportion. We know the original price is 100 and the sale price is 70. So, we set up the equation like this:

*100/x = 70/100*

We can cross multiply to solve for x. When we do that, we get the following:

*x = 100*70/100 = $70*

So, the sale price of the shoes is $70.

### Finding the simple interest and compound interest

If you need to calculate the interest on a loan, you can use the Proportion calculator to find the simple interest and compound interest. All you need is to know the loan amount, the interest rate, and the years you will pay off the loan.

The Proportion calculator will give you the answer in two different ways. The first way is to show you the total interest you will pay over the life of the loan. The second way is to show you the interest you will pay each year.

### Proportion word problems

You can use proportions to solve word problems in many different situations.

Example

The ratio of apples to oranges in a certain fruit basket is 2:3. If there are 12 oranges, how many apples are there?

First, identify the known values and unknown values. In this problem, the known values are the ratio of apples to oranges and the number of oranges. The unknown value is the number of apples. We can set up the proportion *2/3 = x/12*, where x represents the number of apples.

Next, we will cross-multiply to solve for x.

*24/3 = x*

*x = 8*

Therefore, there are 8 apples in the fruit basket.

## Applications of Proportions in Real life

You can use proportions in many different ways in everyday life. Some examples might include cooking, measuring ingredients for a recipe, creating a budget, and figuring out how much money can be spent on different items.

## Conclusion

If you're still not sure what proportion is or how to calculate it, don't worry! Just remember that a proportion is simply a way to compare two ratios. And the easiest way to calculate a proportion is to use a proportion calculator.