A generalisation is a statement or rule that applies correctly to all relevant cases.

A denominator is the bottom number in a fraction. It shows how many parts a whole has been divided into.

A numerator is the top number in a fraction. It shows how many parts we have.

Add fractions with the same denominator and generalise the rule

Maths

In this unit pupils will use repeated addition of a unit fraction to form a non-unit fraction. They will compare non-unit fractions with the same denominator. They will add and subtract fractions with the same denominator. In the future unit pupils will identify equal parts when they do not look the same related to equivalence. They will construct a whole when given a part and the number of parts.

In the prior unit pupils explained that non-unit fractions are composed of more than one unit fraction using knowledge of unit fractions to find one whole. In this unit pupils will use repeated addition of a unit fraction to form a non-unit fraction. They will compare non-unit fractions with the same denominator. They will add and subtract fractions with the same denominator.

Composition of non-unit fractions: addition and subtraction

Look at the image. What is the missing label marked with a question mark?

Look at the number line. The missing addend is ___ 

$$ \frac{1}{8} $$ + $$ \frac{4}{8} $$ = $$ \frac{3}{8} $$ 

$$ \frac{6}{8} $$ + $$ \frac{5}{8} $$ = $$ \frac{1}{8} $$

$$ \frac{3}{8} $$ + $$ \frac{3}{8} $$ = $$ \frac{6}{8} $$

$$ \frac{1}{8} $$ + $$ \frac{3}{8} $$ = $$ \frac{4}{8} $$

What addition is being represented on this number line?

What is the sum of this equation?
$$ \frac{3}{7} $$ + $$ \frac{2}{7} $$ + $$ \frac{1}{7} $$ = ___

What is the correct sum for this equation?
___ = $$ \frac{4}{20} $$ + $$ \frac{6}{20} $$+ $$ \frac{6}{20} $$

Which of the following numbers could be used to complete this inequality? 

Which of these definitions describes the sum?

What is the missing number in this bar model?

What addition is being shown by this number line?

Each marble in a bag is $$ \frac{1}{9} $$ of the whole bag. How many marbles are there in the bag?

What is the missing fraction in this bar model?

Select the correct sum. $$ \frac{2}{7} $$ + $$ \frac{4}{7} $$ = ___

Starter Quiz