Why are they called improper?

The name is very old. A proper fraction was seen as a true part of one whole, and a fraction that is a whole or more did not fit that idea, so it was called improper. It does not mean wrong.

Can every whole number be written as an improper fraction?

Yes. Multiply the whole number by any denominator to get the numerator: $3 = \frac{3}{1} = \frac{6}{2} = \frac{12}{4}$.

Do I always have to change an improper fraction into a mixed number?

No. Both forms are correct. Improper fractions are usually easier for calculating, while mixed numbers like $1\frac{3}{4}$ show the size at a glance. Changing between the two forms is the topic of the next lessons.

Teacher Resources

Improper Fractions

Q: Is $\frac{4}{4}$ a proper or an improper fraction?

It is improper. A proper fraction must be less than 1, but $\frac{4}{4}$ is exactly 1. Every fraction whose numerator equals its denominator is improper and equal to 1.

Learn what improper fractions are, how they differ from proper fractions, and why they are equal to or greater than 1.

Elementary20 minLesson

Printable worksheet

Definition

An improper fraction is a fraction whose numerator is greater than or equal to its denominator. Examples:

\frac{5}{4}

\frac{7}{3}

\frac{6}{6}

A proper fraction has a numerator smaller than its denominator, like

\frac{3}{4}

. A proper fraction is always less than 1.

To tell them apart, compare the numerator with the denominator:

Numerator smaller than the denominator: proper, less than 1 ( $\frac{3}{4} < 1$ )
Numerator equal to the denominator: improper, exactly 1 ( $\frac{4}{4} = 1$ )
Numerator greater than the denominator: improper, more than 1 ( $\frac{7}{4} > 1$ )

Think of

\frac{7}{4}

as seven quarters. Four quarters make one whole, and three quarters are left over:

\frac{7}{4} = \frac{4}{4} + \frac{3}{4} = 1 + \frac{3}{4}

When the numerator is a multiple of the denominator, the improper fraction is a whole number:

\frac{6}{3} = 6 \div 3 = 2

Try it now

Which fraction is improper?

Worked Examples

Sort these fractions: $\frac{3}{5}$ , $\frac{8}{5}$ and $\frac{5}{5}$ . Which are proper and which are improper?

Look at $\frac{3}{5}$

Numerator $3$ , denominator $5$ : $3 < 5$ → Proper, less than 1

Look at $\frac{8}{5}$

Numerator $8$ , denominator $5$ : $8 > 5$ → Improper, more than 1

Look at $\frac{5}{5}$

$5 = 5$ , so all five fifths together make one whole → Improper, exactly 1

Answer: $\frac{3}{5}$ is proper. $\frac{8}{5}$ and $\frac{5}{5}$ are improper, and $\frac{5}{5} = 1$ .

Common Mistakes

Thinking a fraction can never be greater than 1

Why it's wrong: Fractions are often introduced as parts of one whole, so it seems impossible to have more parts than the whole has. But a fraction counts equal parts, and you can count more parts than fit into one whole.

Correct: $\frac{7}{4}$ means seven quarters: one whole (four quarters) plus three more quarters, so $\frac{7}{4} > 1$ .

Calling $\frac{4}{4}$ a proper fraction

Why it's wrong: It looks like an ordinary fraction, but a proper fraction must be less than 1, and $\frac{4}{4}$ is exactly 1.

Correct: When the numerator equals the denominator, the fraction is improper and equal to 1: $\frac{4}{4} = \frac{9}{9} = 1$ .

Putting $\frac{5}{4}$ between 0 and 1 on the number line

Why it's wrong: Many students stop counting quarters at 1. But after $\frac{4}{4}$ the jumps simply keep going, and $\frac{5}{4}$ is the next mark.

Correct: Keep counting past 1: $\frac{4}{4} = 1$ , so $\frac{5}{4}$ is one quarter to the right of 1.

Thinking improper means wrong

Why it's wrong: In everyday language improper sounds like a mistake, but in math it is only the name for fractions that are 1 or more.

Correct: $\frac{9}{4}$ is a perfectly correct answer. Often it is the most useful form for calculating.

Interactive Visual

Numerator:

Denominator:

7/4=134= 175%

Click on the bar to change the fraction

Fraction Number Line

Denominator

Click on tick marks to select fractions.

Interactive Sandbox

Expression Calculator

Try these:

History

No calculations yet

Practice Problems

18 problems

Problem 1 of 18

Easy

Which fraction is improper?

Why It Matters

Amounts bigger than one whole are everywhere, and improper fractions describe them by counting equal parts:

Cooking: Six quarter cups of flour are $\frac{6}{4}$ cups, more than one cup
Time: Five quarter hours are $\frac{5}{4}$ of an hour, which is 75 minutes
Sharing food: Eating 9 slices from pizzas cut into 8 slices each means eating $\frac{9}{8}$ of a pizza
Adding fractions: $\frac{3}{4} + \frac{3}{4} = \frac{6}{4}$ , so answers often come out improper

Improper fractions are also the easiest form to calculate with, which is why you will meet them again and again when you add, multiply and divide fractions.

Real World Applications

Cooking with Measuring Scoops

Recipes are often measured with small scoops, and several scoops easily add up to more than one cup.

Example:

Three scoops of $\frac{1}{2}$ cup of milk are $\frac{3}{2}$ cups, which is more than 1 cup.

1Try It Yourself

Your only measuring scoop holds $\frac{1}{4}$ cup. A pancake recipe needs 6 scoops of flour.

How many cups of flour is that, written as a fraction?

Step 1: Write the mathematical expression

Count the quarter cups:

Time in Quarter Hours

A quarter hour is 15 minutes, so timetables and schedules often count time in quarters of an hour.

Example:

A film that lasts 6 quarter hours lasts $\frac{6}{4}$ of an hour, which is 90 minutes.

2Try It Yourself

Swimming practice lasts 5 quarter hours.

What fraction of an hour is that, and how many minutes?

Step 1: Write the mathematical expression

Five quarter hours of 15 minutes each:

Water Bottles for a Team

Drinks are often sold in half liter bottles, and a few bottles quickly add up to several liters.

Example:

Two half liter bottles hold $\frac{2}{2} = 1$ liter of water.

3Try It Yourself

A football team brings 7 bottles, each holding $\frac{1}{2}$ liter of water.

How many liters of water is that, written as a fraction?

Step 1: Write the mathematical expression

Count the half liters:

Key Takeaways

1An improper fraction has a numerator greater than or equal to its denominator, like $\frac{7}{4}$ or $\frac{5}{5}$
2A proper fraction has a smaller numerator than denominator and is always less than 1
3If the numerator equals the denominator, the fraction is exactly 1: $\frac{6}{6} = 1$
4If the numerator is greater, the fraction is more than 1 and lies to the right of 1 on the number line
5If the numerator is a multiple of the denominator, the fraction is a whole number: $\frac{6}{3} = 2$
6Improper is only a name, not a mistake. $\frac{7}{4}$ can also be written as the mixed number $1\frac{3}{4}$ , which comes in the next lessons

Frequently Asked Questions

It is improper. A proper fraction must be less than 1, but

\frac{4}{4}

is exactly 1. Every fraction whose numerator equals its denominator is improper and equal to 1.

Glossary

Proper fraction: A fraction whose numerator is smaller than its denominator, like $\frac{3}{4}$ . It is always less than 1.
Improper fraction: A fraction whose numerator is greater than or equal to its denominator, like $\frac{7}{4}$ or $\frac{4}{4}$ . It is 1 or more.
Numerator: The top number of a fraction; it counts how many equal parts there are
Denominator: The bottom number of a fraction; it tells how many equal parts make one whole
Whole number: One of the numbers 0, 1, 2, 3 and so on. Some improper fractions are whole numbers, like $\frac{6}{3} = 2$ .
Mixed number: A whole number and a proper fraction written together, like $1\frac{3}{4}$ . It is another way to write an improper fraction.

Formula Card

Proper fraction

\frac{a}{b} < 1 \text{ if } a < b

The numerator is smaller than the denominator

Equal to one

\frac{a}{a} = 1

The numerator equals the denominator, so the fraction is improper and equal to 1

Greater than one

\frac{a}{b} > 1 \text{ if } a > b

The numerator is greater than the denominator, so the fraction is improper

Whole number

\frac{a}{b} = a \div b

If $b$ divides $a$ exactly, the fraction is a whole number, for example $\frac{12}{4} = 3$

Improper Fractions

Definition

Worked Examples

Common Mistakes

Interactive Visual

Fraction Number Line

Interactive Sandbox

Expression Calculator

History

Practice Problems

Why It Matters

Real World Applications

Cooking with Measuring Scoops

Time in Quarter Hours

Water Bottles for a Team

Key Takeaways

Frequently Asked Questions

Glossary

Formula Card

Proper fraction

Equal to one

Greater than one

Whole number

More in This Topic

What Are Fractions

Equivalent Fractions

Simplifying Fractions

Introduction to Mixed Numbers