How do you calculate a ratio for beginners?

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This ratio calculator will accept integers, decimals and scientific e notation with a limit of 15 characters.

Simplify Ratios:

Enter A and B to find C and D. (or enter C and D to find A and B)
The calculator will simplify the ratio A : B if possible. Otherwise the calculator finds an equivalent ratio by multiplying each of A and B by 2 to create values for C and D.

Compare Ratios and Solve for the Missing Value:

Enter A, B and C to find D.
The calculator shows the steps and solves for D = C * (B/A)

Enter A, B and D to find C.
The calculator shows the steps and solves for C = D * (A/B)

Evaluate Equivalent Ratios:

Enter A, B, C and D.
Is the ratio A : B equivalent to the ratio C : D? The calculator finds the values of A/B and C/D and compares the results to evaluate whether the statement is true or false.

Convert Ratio to Fraction

A part-to-part ratio states the proportion of the parts in relation to each other. The sum of the parts makes up the whole. The ratio 1 : 2 is read as "1 to 2." This means of the whole of 3, there is a part worth 1 and another part worth 2.

To convert a part-to-part ratio to fractions:

  1. Add the ratio terms to get the whole. Use this as the denominator.
    1 : 2 => 1 + 2 = 3
  2. Convert the ratio into fractions. Each ratio term becomes a numerator in a fraction.
    1 : 2 => 1/3, 2/3
  3. Therefore, in the part-to-part ratio 1 : 2, 1 is 1/3 of the whole and 2 is 2/3 of the whole.

To reduce a ratio to lowest terms in whole numbers see our Ratio Simplifier.

To simplify a fraction into a reduced fraction or mixed number use our Simplifying Fractions Calculator.

To calculate the ratio of an amount we divide the amount by the total number of parts in the ratio and then multiply this answer by the original ratio.

How do you calculate a ratio for beginners?

How do you calculate a ratio for beginners?

    • We want to work out $20 shared in the ratio of 1:3.
  • Step 1 is to work out the total number of parts in the ratio.

 

  • 1 + 3 = 4, so the ratio 1:3 contains 4 parts in total.

 

  • Step 2 is to divide the amount by the total number of parts in the ratio.

 

  • $20 ÷ 4 = $5.

 

  • Each of the four parts of the ratio is worth $5.

 

  • Step 3 is to scale up our original ratio by the value of each part.

 

  • 1:3 multiplied by $5 becomes $5:$15.

 

  • One person gets $5 and the other gets $15.

 

  • We can check our ratio calculation by adding $5 and $15 to get our total amount of $20.

 

How do you calculate a ratio for beginners?

Supporting Lessons

  • Sharing in a Ratio: Part 1
  • Sharing in a Ratio: Part 2


How do you calculate a ratio for beginners?

Calculating a Ratio of an Amount: Interactive Questions

Calculating a Ratio of an Amount: Interactive Questions

Calculating a Ratio of an Amount Worksheets and Answers

How do you calculate a ratio for beginners?

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How do you calculate a ratio for beginners?

Download PDF

How to Calculate a Ratio of a Number

What is a Ratio?

Ratios describe how to share out a given amount and are written with numbers separated by colons. The amount of numbers in the ratio tells us how many groups the quantity is being shared between. The size of each number tells us the proportion of the total amount each group gets.

For example, in the ratio 1:3 there are two different numbers: ‘1’ and ‘3’.

Because there are two numbers, we are sharing an amount between two people.

This ratio means that for every 1 part that the person on the left gets, the person on the right gets 3. The person on the right will have three times as much as the person on the left.

How do you calculate a ratio for beginners?

The person on the left will get $5 and the person on the right will get $15. Both numbers add to make the total of $20 but $15 is three times larger than $5. This is why the ratio is 1 to 3.

How to Calculate a Ratio of a Number in Steps

To calculate a ratio of a number, follow these 3 steps:

  1. Add the parts of the ratio to find the total number of parts.
  2. Find the value of each part of the ratio by dividing the number by the total number of parts calculated in step 1.
  3. Multiply each part of the original ratio by the value of each part calculated in step 2.

For example, share $20 in the ratio 1:3.

How do you calculate a ratio for beginners?

This means that in this ratio problem, we will be sharing $20 between two people with one person getting three times as much as the other.

We follow the 3 steps above to work out the ratio.

  • Step 1: Find the total number of parts

How do you calculate a ratio for beginners?

Looking at the ratio 1:3, we have:

1 + 3 = 4

So, we have four parts in total in our ratio.

  • Step 2: Divide the amount by the total number of parts

How do you calculate a ratio for beginners?

The amount is $20 and the total number of parts is 4.

20 ÷ 4 = 5

Each of the four parts is worth $5.

  • Step 3: Multiply each number in the ratio by the value of one part

How do you calculate a ratio for beginners?

We have four parts in total and each of these parts are worth $5.

We will multiply both numbers in the ratio 1:3 by $5.

1 x $5 = $5

3 x $5 = $15

The money is shared in the ratio $5:$15.

We have solved our ratio problem to find that one person gets $5 and the other person gets $15.

To check a ratio calculation, add the final values to see if the total is equal to the original amount. If the amounts shared can also be simplified to make the ratio given, the calculation is correct.

$5 + $15 = $20, which is the amount that we started with, so we can be confident that our calculation is correct.

To confirm our ratio calculation, we check that $5:$15 simplifies to give us our original ratio.

Dividing both $5 and $15 by 5, gives us 1:3, which is our original ratio and $15 is indeed three times as much as $5.

How do you calculate a ratio for beginners?

Now try our lesson on Sharing in a Ratio Between 3 People where we learn how to extend our steps for calculating ratio to examples where we share an amount between 3 people.

How do you calculate ratio for dummies?

A ratio is an ordered pair of numbers a and b, written a / b where b does not equal 0..
1 : 3 (for every one boy there are 3 girls).
1 / 4 are boys and 3 / 4 are girls..
0.25 are boys (by dividing 1 by 4).
25% are boys (0.25 as a percentage).

How do you do ratios in math step by step?

To calculate a ratio of a number, follow these 3 steps:.
Add the parts of the ratio to find the total number of parts..
Find the value of each part of the ratio by dividing the number by the total number of parts calculated in step 1..
Multiply each part of the original ratio by the value of each part calculated in step 2..

What is the ratio formula?

Ratio Formula The general form of representing a ratio of between two quantities say 'a' and 'b' is a: b, which is read as 'a is to b'. The fraction form that represents this ratio is a/b. To further simplify a ratio, we follow the same procedure that we use for simplifying a fraction. a:b = a/b.

What are 3 ways to find a ratio?

Step 1: Find the total number of parts in the ratio by adding the numbers in the ratio together. Step 2: Find the value of each part in the ratio by dividing the given amount by the total number of parts. Step 3: Multiply the original ratio by the value of each part.