## What you need to know

**Things to remember:**

- We can have positive, negative, and improper fractions.
- We can convert between mixed numbers and improper fractions to help add and subtract.

** **

Fractions with like denominators are fractions with the same denominator, which we know how to add and subtract; we add and subtract the numerators, the denominators don’t change.

\dfrac{2}{9}+\dfrac{3}{9}=\dfrac{2+3}{9}=\dfrac{5}{9}

\dfrac{15}{24}-\dfrac{11}{24}=\dfrac{15-11}{24}=\dfrac{4}{24}=\dfrac{1}{6}

*Write \dfrac{5}{11}+\dfrac{9}{11} as a single fraction and as a mixed number.*

* *

\frac{5}{11}+\frac{9}{11}=\frac{5+9}{11}=\frac{14}{11}

*Tip: **To turn an improper fraction into a mixed number, we divide like normal. The whole number part of the division is the whole number part of the mixed number, and the remainder goes over the original denominator.*

\frac{5}{11}+\frac{9}{11}=\frac{14}{11}=1\frac{3}{11}

Like with whole number, we can add more than two fractions together.

*Write \dfrac{5}{11}+\dfrac{9}{11}+\dfrac{10}{11} as a single fraction and as a mixed number.*

\frac{5}{11}+\frac{9}{11}+\frac{10}{11}=\frac{5+9+10}{11}=\frac{24}{11}

\frac{5}{11}+\frac{9}{11}+\frac{10}{11}=\frac{24}{11}=2\frac{2}{11}

We do the exact same when subtracting fractions as well.

*Write \dfrac{3}{15}-\dfrac{14}{15}-\dfrac{13}{15} as a single fraction and as a mixed number.*

\frac{2}{15}-\frac{14}{15}-\frac{13}{15}=\frac{2-14-13}{15}=-\frac{25}{15}

\frac{3}{15}-\frac{14}{15}-\frac{13}{15}=-\frac{25}{15}=-\frac{5}{3}=-1\frac{2}{3}

## KS3 Maths Revision Cards

(78 Reviews) £8.99## Example Questions

**Question 1:** Write the following as a single fraction and mixed number

\frac{3}{5}+\frac{4}{5}+\frac{2}{5}

\frac{3}{5}+\frac{4}{5}+\frac{2}{5}=\frac{3+4+2}{5}=\frac{9}{5}

\frac{3}{5}+\frac{4}{5}+\frac{2}{5} =\frac{9}{5}=1\frac{4}{5}

**Question 2:** Write the following as a single fraction.

\frac{19}{24}-\frac{7}{24}-\frac{2}{24}

frac{19}{24}-\frac{7}{24}-\frac{2}{24}=\frac{19-7-2}{24}=\frac{10}{24}

## KS3 Maths Revision Cards

(78 Reviews) £8.99- All of the major KS2 Maths SATs topics covered
- Practice questions and answers on every topic

- Detailed model solutions for every question
- Suitable for students of all abilities.