A mixed number is a whole number and a fraction combined.

An improper fraction is a fraction where the numerator is greater than or equal to the denominator.

Solve problems involving addition and subtraction of mixed numbers

Maths

Add mixed numbers crossing the whole

Subtract a proper fraction from a mixed number crossing the whole

Subtract a mixed number from a mixed number

Choose efficient approaches when subtracting mixed numbers

In this unit pupils will add mixed numbers. They subtract a proper fraction from a mixed number and subtract a mixed number from a mixed number explaining which strategy is most efficient. In the future unit pupils will explain the relationship between repeated addition of a proper fraction and multiplication of fractions They will multiply a proper fraction by a whole number.

In the prior unit pupils expressed and converted a quantity from an improper fraction to a mixed number and explained how a mixed number was converted into an improper fraction. In this unit pupils will add mixed numbers. They will subtract a proper fraction from a mixed number and subtract a mixed number from a mixed number explaining which strategy is most efficient..

In this unit pupils will add mixed numbers. They will subtract a proper fraction from a mixed number and subtract a mixed number from a mixed number explaining which strategy is most efficient.

Efficient strategies for adding and subtracting mixed numbers (crossing a whole)

Which bar model represents this problem? Izzy eats one and one-quarter slices of pizza. How much less pizza does she eat than Andeep who has eaten two and three-quarter slices of pizza?

Look at the table. How far does Izzy walk over Monday and Tuesday in all?

Look at the table. How far does Izzy walk over Tuesday and Wednesday in total?

Look at the table. How much further does Izzy walk on Wednesday than Thursday?

Andeep has a five and five-tenths metres of rope. He cuts a piece off. He has three and two-tenth metres left. What length of rope did he cut off?

Izzy spends two and three-quarter hours in the park on Saturday and another two and two-quarter hours on Sunday. How long does she spend in the park in total?

Look at this calculation: $$ {4} \over {10}$$ − $$ {3} \over {10}$$ What is the unit we are working with? 

$$2{{4} \over {5}}$$ + $$1{{3} \over {5}}$$ =

$$3{{4} \over {5}}$$ − $$1{{3} \over {5}}$$ =

Use ‘finding the difference’ by counting on to solve $$8{{2} \over {9}}$$ − $$7{{8} \over {9}}$$

Match the mixed number to their equivalent improper fraction.

By expressing the mixed numbers as improper fractions, calculate this:  $$7{{3} \over {8}}$$ − $$2{{5} \over {8}}$$ =

Solve problems involving addition and subtraction of mixed numbers

Lesson outcome