Calculate one subtraction with aligned place values.
Free to use and free to share. There is no sign-up, no score, and nothing a child does here is recorded or sent anywhere.
Practise it now
Drag the number bricks into the bar model, then read off the answer.
This exercise practises subtract whole numbers or decimals alongside its own main skill, Bar Models: Missing Part.
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.
Subtracting from a value read off the line
Point C is marked on the number line. What is the value at C minus 1.8?
Each small step on this line is worth 0.1, and every labelled tick is ten steps on.
5.3
6.3
4.5
6.2
Answer: 6.3
How you get there
C sits at 8.1, so the calculation is 8.1 - . Line the decimal points up under each other, not the last digits, and where the top digit is the smaller one you have to borrow from the column to its left rather than swapping the two digits round.
Why the other answers tempt
A column where the top digit is smaller needs a borrow; it is not a signal to swap the two digits round.
If they are stuck, say this
Work out what C is worth first by counting the small steps on from the labelled tick before it, then take 1.8 away from it.
Every brick is the two bricks below it added together. Tap a gap and fill in all three.
This engine’s own main skill is Number Pyramid. It practises subtract whole numbers or decimals alongside it.
A number pyramid is just addition stacked up, but the order matters. Each brick needs BOTH bricks underneath it before you can work it out, so you always build from the bottom up. Here the bottom row 3, 5, 2, 6 gives 8, 7, 8 on the next row, then 15 and 15, and finally 30 on top. When a gap looks impossible, it is almost always because a brick below it is still missing. Fill that one first and the rest falls out.
What to say if they get stuck
Start at the bottom. A gap can only be filled once you can see both bricks holding it up.
The gap on the third row sits directly on 5 and 2 from the bottom row.
With the third row finished you have 8, 7, 8. That gives and on the next row, and the capstone is those two added together.
How subtract whole numbers or decimals 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: calculate one subtraction with aligned place values, and it stops where operation is supplied.
Questions parents ask about subtract whole numbers or decimals
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.
Calculate one subtraction with aligned place values. It is one of 55 named maths skills in the 11+, in the number strand, and this page carries 2 interactive exercises that practise it.
A column where the top digit is smaller needs a borrow; it is not a signal to swap the two digits round. 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. Work out what C is worth first by counting the small steps on from the labelled tick before it, then take 1.8 away from it.
The skill map draws the line here: Operation is supplied. 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 subtract whole numbers or decimals are add whole numbers or decimals, calculate a whole-number operation and compare and order numbers. Each has its own exercise and its own link, and none of them needs an account.
Use Bar Model Builder and Build the Wall, embedded on this page. They are the exercises the skill map attaches to subtract whole numbers or decimals, they run in the browser with no account to make, nothing is scored, and nothing a child does here is recorded or sent anywhere. Each also has its own link, so you can send one 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.
