What does a child have to do to evaluate a mixed expression in the 11+?

Apply operation order to a supplied numerical expression. It is one of 55 named maths skills in the 11+, in the number strand, and this page carries 1 interactive exercise that practises it.

Why does my child keep getting evaluate a mixed expression questions wrong?

There is a specific mistake recorded against this skill: evaluates every operation from left to right. 11+ papers are written to offer exactly that answer, so a child can be confident and still lose the mark. When it keeps happening, the fix is the misunderstanding rather than more questions.

What can I say if my child is stuck on evaluate a mixed expression?

Point at the next move rather than explaining the whole rule. Read all three points off the line first, then decide which part of R + P ÷ C has to be worked out before the rest.

What is not part of evaluate a mixed expression in the 11+?

The skill map draws the line here: No unknown quantity. A question past that line is testing a different named maths skill, which is worth knowing before you spend a week practising the wrong one.

Which other 11+ skills should we practise alongside evaluate a mixed expression?

The number strand holds 13 skills that are tested together, and the pages next to evaluate a mixed expression are find a sequence term, multiply whole numbers or decimals and read place value. Each has its own exercise and its own link, and none of them needs an account.

How can my child practise evaluate a mixed expression for free?

Use BIDMAS Machine, embedded on this page. It is the exercise the skill map attaches to evaluate a mixed expression, it runs in the browser with no account to make, nothing is scored, and nothing a child does here is recorded or sent anywhere. It also has its own link, so you can send it to a child without sending them anywhere else first.

Maths · Number

Evaluate a mixed expression

Apply operation order to a supplied numerical expression.

Practise it now

Work the expression out one operation at a time. Tap the operation that has to happen next.

Loading the interactive exercise. Nothing you do here is saved or scored.

A worked example

One question of the kind this skill is tested with, worked all the way through: the reasoning, and what the wrong answers are there to catch.

Deciding what comes first

Points R, P and C are marked on the number line. Work out R + P ÷ C.

Each small step on this line is worth 1, and every labelled tick is ten steps on.

Answer: 30

How you get there

Reading the line gives R is 26, P is 8 and C is 2, so R + P ÷ C comes to 30, because division is worked out before addition. Working straight across from left to right gives a different number, which is why the order has to be decided before any of it is calculated.

Why the other answers tempt

A calculation is not worked out in the order it is written; the order of operations decides it.

If they are stuck, say this

Read all three points off the line first, then decide which part of R + P ÷ C has to be worked out before the rest.

Now do it live in BIDMAS Machine

Kitchen-table script for parents

Try this together

A friendly mini script for the breakfast table, school run or a quiet two minutes. Read it aloud as written, or make it your own.

Ready? Let's have a go at Evaluate a mixed expression together. Take a look at the picture. Here is what matters: Number line from 0 to 40 in steps of 1 with major steps of 10. Here comes the question: Points R, P and C are marked on the number line. Work out R + P ÷ C. Before we race ahead, let us choose one good first step. Here is a helpful clue: Read all three points off the line first, then decide which part of R + P ÷ C has to be worked out before the rest. Nice work. Now let us follow the thinking: Working straight across from left to right gives a different number, which is why the order has to be decided before any of it is calculated. So our answer is: 30. There is one sneaky trap to watch for: A calculation is not worked out in the order it is written; the order of operations decides it. Can you show me that first move again in your own words? Brilliant. No rush; we are practising a method you can reuse, not trying to win a speed contest.

What this exercise is doing

BIDMAS Machine

Work the expression out one operation at a time. Tap the operation that has to happen next.

Brackets come first, so $17 + 64 = 81$ before anything else happens. That leaves the rest of the line to finish, and $(17 + 64) \div 9 + 9 \times 8$ comes to 81. Reading it straight from left to right gives 144 instead, which is why the order is the whole question.

What to say if they get stuck

Anything inside brackets is a parcel. It has to be opened before the rest of the line can move.
Multiplying and dividing happen before adding and subtracting, however far along the line they sit.
Reading straight from left to right gives 144, which is not the same thing.

Open BIDMAS Machine on its own page to share it

What usually goes wrong here

Evaluates every operation from left to right.

This is the wrong answer 11+ papers are built to offer, so it is worth watching for directly: a child who does this will look confident and still lose the mark. If it keeps happening on evaluate a mixed expression, the fix is the misunderstanding rather than more questions.

How evaluate a mixed expression differs from the skills beside it

The same exercise practises one other skill, and telling them apart is often the difficulty rather than the exercise itself. On this page the skill is: apply operation order to a supplied numerical expression, and it stops where no unknown quantity.

Calculate a whole-number operation
Calculate one stated addition, subtraction, multiplication, or division. Excludes choosing the operation from a multi-step context.

Related maths skills

Add whole numbers or decimalsCalculate one addition with aligned place values.
Compare and order numbersOrder or compare a bounded set of integers or decimals.
Continue a number sequenceInfer and apply one arithmetic sequence rule.
Divide whole numbers or decimalsCalculate one division and interpret any remainder as stated.
Find a sequence termUse a stated or inferred linear rule to find a named term.
Multiply whole numbers or decimalsCalculate one multiplication using place-value reasoning or a written method.
Read place valueState the value of one digit in an integer or decimal.
Round to a stated placeRound one integer or decimal to the stated place value.
Scale by a power of tenMultiply or divide a number by 10, 100, or 1000 using place value.
Solve a one-step number problemChoose and perform one operation in a short context.
Subtract whole numbers or decimalsCalculate one subtraction with aligned place values.

All maths 11+ skills

Questions parents ask about evaluate a mixed expression

Answered from what the skill map records about this skill, not from a template. Every answer here is on the page, and the same questions are the page's FAQ structured data.

: Apply operation order to a supplied numerical expression. It is one of 55 named maths skills in the 11+, in the number strand, and this page carries 1 interactive exercise that practises it.
: There is a specific mistake recorded against this skill: evaluates every operation from left to right. 11+ papers are written to offer exactly that answer, so a child can be confident and still lose the mark. When it keeps happening, the fix is the misunderstanding rather than more questions.
: Point at the next move rather than explaining the whole rule. Read all three points off the line first, then decide which part of R + P ÷ C has to be worked out before the rest.
: The skill map draws the line here: No unknown quantity. A question past that line is testing a different named maths skill, which is worth knowing before you spend a week practising the wrong one.
: The number strand holds 13 skills that are tested together, and the pages next to evaluate a mixed expression are find a sequence term, multiply whole numbers or decimals and read place value. Each has its own exercise and its own link, and none of them needs an account.
: Use BIDMAS Machine, embedded on this page. It is the exercise the skill map attaches to evaluate a mixed expression, it runs in the browser with no account to make, nothing is scored, and nothing a child does here is recorded or sent anywhere. It also has its own link, so you can send it to a child without sending them anywhere else first.

One wrong answer is a slip, the same wrong answer every time is a habit

A free diagnostic looks at which mistakes repeat across all four subjects, not just whether evaluate a mixed expression was right on the day.

Start the free 11+ diagnostic