Converting Fractions to Decimals

Learn how to convert any fraction into a decimal using division.

Elementary20 minLesson
Printable worksheet

Definition

To convert a fraction to a decimal, divide the numerator by the denominator.
Fraction=numeratordenominator=numerator÷denominator\text{Fraction} = \frac{\text{numerator}}{\text{denominator}} = \text{numerator} \div \text{denominator}
For example:
34=3÷4=0.75\frac{3}{4} = 3 \div 4 = 0.75
The fraction bar means division! So 12\frac{1}{2} is the same as 1÷2=0.51 \div 2 = 0.5.

Try it now

What is 12\frac{1}{2} as a decimal?

Worked Examples

Convert 12\frac{1}{2} to a decimal.
1

Set up the division

1÷21 \div 2 → Numerator divided by denominator
2

Perform the division

1÷2=0.51 \div 2 = 0.5
3

Verify your answer

0.5×2=10.5 \times 2 = 1 ✓ → Correct!

Common Mistakes

Dividing the denominator by the numerator instead

Why it's wrong: Students sometimes reverse the division: doing 4÷34 \div 3 instead of 3÷43 \div 4 for 34\frac{3}{4}.

Correct: Always divide the TOP number (numerator) by the BOTTOM number (denominator). Think: the fraction bar means 'divided by'.

Forgetting to add zeros when dividing

Why it's wrong: When 3÷43 \div 4 doesn't work as a whole number, students get stuck.

Correct: Add a decimal point and zeros: 3.00÷4=0.753.00 \div 4 = 0.75. You can always add zeros after a decimal point.

Stopping the division too early

Why it's wrong: Students might write 58=0.6\frac{5}{8} = 0.6 instead of completing the division to get 0.6250.625.

Correct: Keep dividing until there's no remainder OR you see a repeating pattern.

Confusing decimal places with fraction parts

Why it's wrong: Writing 34\frac{3}{4} as 0.340.34 by just placing the numbers.

Correct: You must DIVIDE! 34=3÷4=0.75\frac{3}{4} = 3 \div 4 = 0.75, not 0.340.34.

Interactive Visual

5
5/8= 63%

Click on the bar to change the fraction

Long Division

5÷85 \div 8
5 is smaller than 8, so the answer starts with 0.

Step 1 of 15

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Practice Problems

15 problems
Problem 1 of 15
Easy
What is 12\frac{1}{2} as a decimal?

Why It Matters

Converting between fractions and decimals is essential in everyday life:
  • Shopping: A sale offering 14\frac{1}{4} off is the same as 25% or 0.25 off the price
  • Cooking: A recipe calls for 34\frac{3}{4} cup, but your measuring cup shows decimals (0.75)
  • Sports: A basketball player makes 710\frac{7}{10} of free throws, which is 0.7 or 70%
  • Grades: Scoring 1720\frac{17}{20} on a test equals 0.85 or 85%
Decimals and fractions are two ways to write the same number!

Real World Applications

Shopping Discounts

Stores often express discounts as fractions, but calculators use decimals.

Example:

A jacket costs 80 dollars with 14\frac{1}{4} off. Since 14=0.25\frac{1}{4} = 0.25, the discount is 80×0.25=2080 \times 0.25 = 20 dollars.

1Try It Yourself

A video game is 60 dollars with 15\frac{1}{5} off.

What is the discount amount?

Step 1: Write the mathematical expression

First convert 15\frac{1}{5} to a decimal, then multiply:

Cooking Measurements

Recipes often use fractions, but some measuring cups are marked in decimals.

Example:

A recipe needs 34\frac{3}{4} cup of flour. On a measuring cup marked in decimals, you fill it to the 0.75 line.

2Try It Yourself

You need 58\frac{5}{8} cup of sugar. Your measuring cup shows decimals.

What decimal should you measure to?

Step 1: Write the mathematical expression

Convert 58\frac{5}{8} to a decimal:

Test Scores

Teachers often convert fraction scores to decimals for calculating grades.

Example:

Getting 1820\frac{18}{20} correct means 18÷20=0.918 \div 20 = 0.9 or 90%.

3Try It Yourself

You scored 1725\frac{17}{25} on a quiz.

What is your score as a decimal?

Step 1: Write the mathematical expression

Divide the numerator by the denominator:

Key Takeaways

  • 1To convert a fraction to a decimal, divide the numerator by the denominator
  • 2The fraction bar means 'divided by': ab=a÷b\frac{a}{b} = a \div b
  • 3Add zeros after the decimal point if needed to complete the division
  • 4Common conversions to memorize: 12=0.5\frac{1}{2} = 0.5, 14=0.25\frac{1}{4} = 0.25, 34=0.75\frac{3}{4} = 0.75, 15=0.2\frac{1}{5} = 0.2

Frequently Asked Questions

Some fractions create repeating decimals. For example, 13=0.333...\frac{1}{3} = 0.333... (the 3 repeats forever). We write this as 0.3‾0.\overline{3}. This lesson sticks to fractions whose division ends, like 58=0.625\frac{5}{8} = 0.625.
Some fractions create repeating decimals. For example, 13=0.333...\frac{1}{3} = 0.333... (the 3 repeats forever). We write this as 0.3‾0.\overline{3}. This lesson sticks to fractions whose division ends, like 58=0.625\frac{5}{8} = 0.625.
Yes! For tenths, put the numerator in the tenths place: 710=0.7\frac{7}{10} = 0.7. For hundredths, put the numerator in the hundredths place: 23100=0.23\frac{23}{100} = 0.23.
Understanding WHY division works helps you estimate, check your calculator results, and recognize patterns. Plus, knowing common conversions like 14=0.25\frac{1}{4} = 0.25 saves time!

Glossary

Numerator
The top number in a fraction, showing how many parts you have
Denominator
The bottom number in a fraction, showing how many equal parts make a whole
Terminating decimal
A decimal that ends, like 0.750.75 or 0.6250.625
Equivalent
Having the same value, just written differently (12\frac{1}{2} and 0.50.5 are equivalent)

Formula Card

Fraction to Decimal

ab=a÷b\frac{a}{b} = a \div b

Divide the numerator (top) by the denominator (bottom). Example: $\frac{3}{4} = 3 \div 4 = 0.75$

Today's challengeOne problem, three tries

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