An equation is used to show that one number, calculation or expression is equal to another.

An unknown is a quantity that has a set value but it is represented by a symbol or letter.

The whole is all the parts or everything, the total amount.

A part is a piece or section of the whole.

Solve calculations with missing parts

Maths

Using redistribution with addition of integers

Using redistribution with addition of decimal fractions

Using balanced equations to calculate redistribution

Use a balanced equation to calculate unknown parts

Explain how adjusting one part affects the sum

Solve addition calculations mentally by using known facts

Solve addition calculations mentally by using known facts in a range of contexts

Use equivalence and compensation strategies to solve problems

Use equivalence and compensation strategies to solve addition problems in a range of contexts

In this unit pupils used the concept of same sum to simplify and solve addition problems. In the future unit pupils will solve calculations with missing addends and use the same difference rule to balance equations. They will explain how increasing or decreasing the minuend affects the difference.

In the prior unit pupils identified structures within stories using their knowledge of structures to create stories. They used their knowledge of additive structures to solve problems. In this unit pupils used the concept of same sum to simplify and solve addition problems

In this unit pupils used the concept of same sum to simplify and solve addition problems.

Use equivalence and compensation to simplify and solve addition calculations

A quantity that has a set value represented by a symbol or letter

An answer you give when you don’t know the answer

Which of the following best describes an unknown?

What is the mass of the plasticine on the balance scale?

Without using a written method, calculate the unknown value in the pair of equations shown.

Without using a written method, calculate the unknown.

Tick the two numbers that are complements to 1,000

Tick the two numbers that are decimal complements to 10

What is the missing number in this equation?
{{ }} + 61 = 150

What is the missing number in this equation?
26 + {{ }} + 11 = 70

What is the missing number in this equation?
{{ }} + 45 + 18 = 89 + 6

Starter Quiz

Tick the equivalent expressions.