What does a child have to do to convert decimal and percentage in the 11+?

Convert one decimal to or from a percentage. It is one of 55 named maths skills in the 11+, in the fractions, decimals and percentages strand, and this page carries 1 interactive exercise that practises it.

What should my child be able to do before working on convert decimal and percentage?

The skill map puts convert fraction and decimal first. Decimal equivalence supports percentage conversion. If convert decimal and percentage keeps going wrong, that is the thing to check before doing more of this one.

Why does my child keep getting convert decimal and percentage questions wrong?

There is a specific mistake recorded against this skill: drops or adds the percent sign without scaling by one hundred. 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 convert decimal and percentage?

Point at the next move rather than explaining the whole rule. A percentage counts hundredths, so ask how many hundredths are in 0.15 before you write the % sign.

What is not part of convert decimal and percentage in the 11+?

The skill map draws the line here: Excludes finding a percentage of a 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 convert decimal and percentage?

The skill map connects it to locate an equivalent value. Symbolic equivalence transfers to number-line placement. That skill has its own page here.

How can my child practise convert decimal and percentage for free?

Use Triple Track, embedded on this page. It is the exercise the skill map attaches to convert decimal and percentage, 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 · Fractions, decimals and percentages

Convert decimal and percentage

Convert one decimal to or from a percentage.

Practise it now

Drive the bar to $\frac{3}{8}$ , then work out the same amount as a percentage.

This exercise practises convert decimal and percentage alongside its own main skill, Converting Fractions to Percentages.

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.

From 0.15 to a percentage

Write 0.15 as a percentage.

The bar shows 3 of its 20 equal parts shaded, which is 0.15 of it and therefore 15% of it.

3/20

15%
150%
3%
0.15%

Answer: 15%

How you get there

0.15 of the whole is 15 hundredths, because multiplying by 100 moves the point two places and not one, so 0.15 is 15%.

Why the other answers tempt

Adding a % sign to the decimal does not convert it.

If they are stuck, say this

A percentage counts hundredths, so ask how many hundredths are in 0.15 before you write the % sign.

Now do it live in Triple Track

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 Convert decimal and percentage together. Take a look at the picture. Here is what matters: Fraction bars: 3/20, 3 of 20 equal parts shaded. Here comes the question: Write 0.15 as a percentage. Before we race ahead, let us choose one good first step. Here is a helpful clue: A percentage counts hundredths, so ask how many hundredths are in 0.15 before you write the % sign. Nice work. Now let us follow the thinking: 0.15 of the whole is 15 hundredths, because multiplying by 100 moves the point two places and not one, so 0.15 is 15%. So our answer is: 15%. There is one sneaky trap to watch for: Adding a % sign to the decimal does not convert 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

Triple Track

Drive the bar to $\frac{3}{8}$ , then work out the same amount as a percentage.

This engine’s own main skill is Converting Fractions to Percentages. It practises convert decimal and percentage alongside it.

$\frac{3}{8}$ shades 3 of the 8 pieces of the bar. Dividing 3 by 8 gives exactly 0.375, and "per cent" just means "out of a hundred", so multiplying by 100 gives 37.5%. The three lanes stop at the same place on the board because they are not three amounts: they are one amount written three ways. Nothing was rounded anywhere - 3 divided by 8 stops dead after three decimal places.

Step 1. Line them up. Drag any lane. Land all three on $\frac{3}{8}$ and watch the other two follow.
Step 2. Under the flap. Two lanes are covered. $\frac{3}{8}$ is what percentage?

What to say if they get stuck

Drag any lane and all three move together - they are one amount wearing three names.
$\frac{3}{8}$ means the whole is cut into 8 equal pieces and you take 3.
Per cent means "out of a hundred". Fill the hundred square and count the cells.

Open Triple Track on its own page to share it

What usually goes wrong here

Drops or adds the percent sign without scaling by one hundred.

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 convert decimal and percentage, the fix is the misunderstanding rather than more questions.

Where convert decimal and percentage 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.

Secure this first: Convert fraction and decimal
Decimal equivalence supports percentage conversion.
The same thinking carries into: Locate an equivalent value
Symbolic equivalence transfers to number-line placement.

How convert decimal and percentage differs from the skills beside it

The same exercise practises several skills, and telling them apart is often the difficulty rather than the exercise itself. On this page the skill is: convert one decimal to or from a percentage, and it stops where excludes finding a percentage of a quantity.

Convert fraction and decimal
Convert one familiar fraction to or from a decimal. Excludes percentage conversion.
Convert fraction and percentage
Convert one familiar fraction to or from a percentage. Excludes finding a percentage of a quantity and chained unit conversion.
Locate an equivalent value
Locate a fraction, decimal, or percentage at the same number-line position. One value and one bounded number line.

Related maths skills

Find a fraction of a quantityCalculate one unit or non-unit fraction of a quantity.
Find a percentage of a quantityCalculate one familiar percentage of a quantity.
Identify a represented fractionName the fraction represented by equal parts.
Multiply fractionsMultiply two proper fractions and simplify the result when required.
Recognise equivalent fractionsRecognise two fractions representing the same value.

All maths 11+ skills

Questions parents ask about convert decimal and percentage

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.

: Convert one decimal to or from a percentage. It is one of 55 named maths skills in the 11+, in the fractions, decimals and percentages strand, and this page carries 1 interactive exercise that practises it.
: The skill map puts convert fraction and decimal first. Decimal equivalence supports percentage conversion. If convert decimal and percentage keeps going wrong, that is the thing to check before doing more of this one.
: There is a specific mistake recorded against this skill: drops or adds the percent sign without scaling by one hundred. 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. A percentage counts hundredths, so ask how many hundredths are in 0.15 before you write the % sign.
: The skill map draws the line here: Excludes finding a percentage of a 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 skill map connects it to locate an equivalent value. Symbolic equivalence transfers to number-line placement. That skill has its own page here.
: Use Triple Track, embedded on this page. It is the exercise the skill map attaches to convert decimal and percentage, 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.

Convert decimal and percentage rests on something else being secure first

This skill depends on convert fraction and decimal. A free diagnostic checks those alongside every other maths skill, so you find out whether the problem is here or underneath it.

Start the free 11+ diagnostic