Mixed numbers and improper fractions are two ways to show amounts greater than or equal to one whole. This cheat sheet helps students understand what each form means, how to read fraction models, and how to convert between forms. It is useful for checking homework, building number sense, and avoiding common fraction mistakes.
Students in grades 3-5 can use it as a quick binder reference during practice.
A mixed number has a whole number and a fraction, such as . An improper fraction has a numerator that is greater than or equal to the denominator, such as . To change a mixed number to an improper fraction, use .
To change an improper fraction to a mixed number, divide the numerator by the denominator and write the remainder as the new numerator.
Key Facts
- A mixed number is written as a whole number plus a proper fraction, such as .
- An improper fraction has a numerator greater than or equal to its denominator, such as or .
- To convert to an improper fraction, use .
- To convert to a mixed number, divide to find the whole number, then use the remainder over .
- The denominator tells how many equal parts make one whole, and it stays the same when converting between a mixed number and an improper fraction.
- The fraction is equal to whole because all equal parts are present.
- A proper fraction is less than , so its numerator is less than its denominator, such as .
- A mixed number and an improper fraction can be equivalent, such as .
Vocabulary
- Mixed number
- A number made of a whole number and a fraction, such as .
- Improper fraction
- A fraction with a numerator greater than or equal to its denominator, such as .
- Proper fraction
- A fraction with a numerator less than its denominator, such as .
- Numerator
- The top number in a fraction that tells how many equal parts are being counted.
- Denominator
- The bottom number in a fraction that tells how many equal parts make one whole.
- Remainder
- The amount left over after division, used as the numerator when changing an improper fraction to a mixed number.
Common Mistakes to Avoid
- Adding the whole number to the numerator only is wrong because is not . You must multiply first, so .
- Changing the denominator during conversion is wrong because the size of each equal part stays the same. For , the improper fraction must still have denominator .
- Forgetting the remainder is wrong because it removes part of the amount. Since gives remainder , the mixed number is .
- Thinking every improper fraction is less than is wrong because an improper fraction has at least one whole. For example, and .
- Comparing only the numerators is wrong when denominators are different because the part sizes are not the same. For example, is greater than because fourths are larger than eighths.
Practice Questions
- 1 Convert to an improper fraction.
- 2 Convert to a mixed number.
- 3 Which is greater, or ?
- 4 Explain why is more than whole and how a fraction model could show that.