What does a child have to do to multiply whole numbers or decimals in the 11+?

Calculate one multiplication using place-value reasoning or a written method. 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.

What is the trap in an 11+ multiply whole numbers or decimals question?

When a column makes 10 or more, write its ones digit and carry the tens into the next column; dropping that carry changes the product. The wrong answers on this skill are built out of that, not out of random numbers, so it is worth naming out loud before your child meets it under time pressure.

What can I say if my child is stuck on multiply whole numbers or decimals?

Point at the next move rather than explaining the whole rule. Read what A is worth off the line first, then work out 8 lots of it, one column at a time from the right.

What is not part of multiply whole numbers or decimals in the 11+?

The skill map draws the line here: Excludes selecting multiplication from context. 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 multiply whole numbers or decimals?

The skill map connects it to solve a multi-step problem. A multi-step context may compose a multiplication step. That skill has its own page here.

How can my child practise multiply whole numbers or decimals for free?

Use Roughly Right, embedded on this page. It is the exercise the skill map attaches to multiply whole numbers or decimals, it runs in the browser with no account to make, these exercises are not scored and do not save learner records. The separate quiz sends answers for marking and shows a score, without saving an assessment record. It also has its own link, so you can send it to a child without sending them anywhere else first.

Maths · Number

Multiply whole numbers or decimals

Calculate one multiplication using place-value reasoning or a written method.

Watch the worked example

Open the video page

The Place-Value Multiplication Trick

This video shows how to use place value or a written method to multiply whole numbers or decimals. Watch an 11+ maths question solved step by step.

0:00 / 2:47

Turn on captions with the CC button. Jump to any part with the chapter buttons.

Read the transcript

Keep practising with Trace Learn. Find topics to practise next

Quick quiz: Multiply whole numbers or decimals

10 questions, with feedback after each one. No sign-up needed.

Read the questions in this quiz

Question 1
Point P is marked on the number line. What is the value at P multiplied by 7?
- A.6.48
- B.0.756
- C.7.06
- D.7.56
Question 2
Point B is marked on the number line. What is the value at B multiplied by 5?
- A.213.5
- B.25.62
- C.21.35
- D.2.135
Question 3
Point Q is marked on the number line. What is the value at Q multiplied by 6?
- A.18.13
- B.15.54
- C.15.6
- D.155.4
Question 4
Point C is marked on the number line. What is the value at C multiplied by 5?
- A.43.55
- B.0.55
- C.34.84
- D.4.355
Question 5
Point P is marked on the number line. What is the value at P multiplied by 7?
- A.53.41
- B.53.48
- C.14.64
- D.5.348
Question 6
Point P is marked on the number line. What is the value at P multiplied by 6?
- A.41.76
- B.417.6
- C.41.82
- D.4.176
Question 7
Point C is marked on the number line. What is the value at C multiplied by 8?
- A.17.28
- B.19.35
- C.1.72
- D.17.2
Question 8
Point R is marked on the number line. What is the value at R multiplied by 6?
- A.366.6
- B.42.77
- C.36.66
- D.3.666
Question 9
Point A is marked on the number line. What is the value at A multiplied by 6?
- A.14.32
- B.499.2
- C.49.92
- D.4.992
Question 10
Point Q is marked on the number line. What is the value at Q multiplied by 6?
- A.1.098
- B.10.98
- C.109.8
- D.11.04

Practise it now

Do not work it out exactly. Slide the marker to where you think the answer lands, then lock it in.

This exercise practises multiply whole numbers or decimals alongside its own main skill, Estimation.

It covers most of this skill rather than all of it.

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.

Multiplying a value read off the line

Point A is marked on the number line. What is the value at A multiplied by 8?

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

Answer: 176

How you get there

A sits at 22, so the calculation is $22 \times 8 = 176$ . The multiplier is a single digit, so work along the columns from the right and carry into the next one.

Why the other answers tempt

When a column makes 10 or more, write its ones digit and carry the tens into the next column; dropping that carry changes the product.

If they are stuck, say this

Read what A is worth off the line first, then work out 8 lots of it, one column at a time from the right.

Now do it live in Roughly Right

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 try Multiply whole numbers or decimals together. Take a look at the picture. Here is what matters: Number line from 10 to 40 in steps of 1 with major steps of 10. Here comes the question: Point A is marked on the number line. What is the value at A multiplied by 8? A handy clue is: Read what A is worth off the line first, then work out 8 lots of it, one column at a time from the right. Nice work. Here is the thinking: A sits at 22, so the calculation is 22 × 8 = 176. The multiplier is a single digit, so work along the columns from the right and carry into the next one. So our answer is: 176. One sneaky trap is: When a column makes 10 or more, write its ones digit and carry the tens into the next column; dropping that carry changes the product. Can you show me the first move in your own words? No rush; one calm step is enough.

What this exercise is doing

Roughly Right

Do not work it out exactly. Slide the marker to where you think the answer lands, then lock it in.

This engine’s own main skill is Estimation. It practises multiply whole numbers or decimals alongside it, and covers most of it rather than all.

Estimating is a skill in its own right, and in the 11+ it is your safety net: it tells you instantly whether an answer you have calculated is believable. The trick is to round each number to the nearest ten (or hundred) FIRST, multiply the easy numbers, then nudge. 49 rounds up to 50 and 21 rounds down to 20, so $50 \times 20 = 1000$ . The real answer is 1029, and you got within a whisker of it without doing any long multiplication. Notice the two roundings pulled in opposite directions, which is why the estimate lands so close.

What to say if they get stuck

Round both numbers to something friendly before you slide.
49 is nearly 50, and 21 is nearly 20. Those two are much easier to multiply.
$50 \times 20 = 1000$ , so the marker belongs just above the halfway mark of this line.

Open Roughly Right on its own page to share it

Where multiply whole numbers or decimals sits in the 11+

The 11+ does not test these skills in isolation, and practising one in the wrong order wastes the practice. These are the skills the curriculum map connects this one to.

This is one piece of: Solve a multi-step problem
A multi-step context may compose a multiplication step.

How multiply whole numbers or decimals 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: calculate one multiplication using place-value reasoning or a written method, and it stops where excludes selecting multiplication from context.

Round to a stated place
Round one integer or decimal to the stated place value. The rounding place is explicit.

Related maths skills

Add whole numbers or decimalsCalculate one addition with aligned place values.
Calculate a whole-number operationCalculate one stated addition, subtraction, multiplication, or division.
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.
Evaluate a mixed expressionApply operation order to a supplied numerical expression.
Find a sequence termUse a stated or inferred linear rule to find a named term.
Read place valueState the value of one digit in an integer or decimal.
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 multiply whole numbers or decimals

What this skill involves, common mistakes and ways to practise it at home.

: Calculate one multiplication using place-value reasoning or a written method. 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.
: When a column makes 10 or more, write its ones digit and carry the tens into the next column; dropping that carry changes the product. The wrong answers on this skill are built out of that, not out of random numbers, so it is worth naming out loud before your child meets it under time pressure.
: Point at the next move rather than explaining the whole rule. Read what A is worth off the line first, then work out 8 lots of it, one column at a time from the right.
: The skill map draws the line here: Excludes selecting multiplication from context. 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 skill map connects it to solve a multi-step problem. A multi-step context may compose a multiplication step. That skill has its own page here.
: Use Roughly Right, embedded on this page. It is the exercise the skill map attaches to multiply whole numbers or decimals, it runs in the browser with no account to make, these exercises are not scored and do not save learner records. The separate quiz sends answers for marking and shows a score, without saving an assessment record. It also has its own link, so you can send it to a child without sending them anywhere else first.

Knowing which maths topic to practise is most of the work

A free diagnostic covers arithmetic, fractions, geometry, measure and data handling, and comes back with the topics to spend the next few weeks on.