Wrong order, wrong answer
The Short Answer
Order of operations questions test whether a calculation is done in the right sequence: brackets, then indices, then divide and multiply, then add and subtract. The part that catches strong pupils is that divide and multiply rank equally and are worked left to right, as do add and subtract — and the answer you get from doing them in the wrong order is usually one of the printed options.
What these questions test
Not arithmetic. Sequence.
You can do every calculation in the line perfectly and still get the question wrong, purely because you did them in the wrong order. That is the uncomfortable thing about this topic, and it is exactly why it appears.
The order in full
Brackets. Indices. Divide and Multiply. Add and Subtract.
And here is the part that trips up even strong pupils:
Divide and multiply are equal in rank. Neither goes first because of where its letter sits in BIDMAS. When both appear, you work them left to right.
Add and subtract are equal too, in the same way, left to right.
Equal partners, in practice
Setting it out so the order cannot slip
Number every operation above the calculation before you work anything out.
Then one operation per line, rewriting the whole calculation each time, until a single number is left.
At Year 5 pace the temptation is to do two steps in your head at once to save time. Don't. The extra line takes three seconds. The mistake takes the mark.
Estimate first
In multiple choice, a rough estimate before calculating usually eliminates two options in about two seconds — and it tends to catch the wrong-order answer, which is often not slightly off but wildly off.
Where do pupils lose marks?
Working straight left to right. 8 + 4 × 5 − 2 is 26, not 58.
Believing divide beats multiply because of the letter order in BIDMAS.
Doing the addition before the subtraction when both are present.
Ignoring what an index is touching — in (6 + 3)² the bracket is squared, but in 6 + 3² only the three is.
Try it yourself
Number each operation above the calculation before you work anything out.
- What is 6 + 7 × 3?
- What is 8 + 4 × 5 − 2?
- What is 60 ÷ (7 + 5) × 2?
- What is (6 + 3)² ÷ 9?
- What is 20 − 4 × 3 + 5?
- 27. The multiplication happens first: 7 × 3 is 21, and then the 6 joins in. Working left to right gives 39, which is 13 × 3.
- 26. Multiply first — 4 × 5 is 20 — then add and subtract left to right: 8 + 20 − 2. Left to right throughout gives 58.
- 10. The bracket gives 12, and then divide and multiply are equal partners worked left to right: 60 ÷ 12 = 5, then 5 × 2 = 10. Multiplying first gives 60 ÷ 24, which is 2.5, and 2.5 will be one of the options.
- 9. Brackets, then indices, then divide: 6 + 3 is 9, nine squared is 81, and 81 ÷ 9 is 9. B, then I, then D, in that order.
- 13. The multiplication first — 4 × 3 is 12 — then 20 − 12 + 5, worked left to right. Doing the addition before the subtraction gives 3.
How much practice does this type need at home?
Short and frequent beats long. Five calculations a day, each one written out line by line, does more than a page once a week — because the skill being built is a habit of setting out, and habits are built by repetition rather than by volume.
One useful question to ask over their shoulder: which two things are you choosing between right now, and why does that one go first?
Free: a Maths workbook
Questions across the Maths question types, with the method printed at the top and full answers at the back. One workbook for the whole strand, not a sheet per question type.
Frequently Asked Questions
Does divide really come before multiply?
No, and this is the misconception BIDMAS itself creates. Divide and multiply are equal in rank; when both appear you work them left to right. In 60 ÷ (7 + 5) × 2, the bracket gives 12, then 60 ÷ 12 is 5 and 5 × 2 is 10. Doing the multiplication first gives 2.5. Add and subtract work exactly the same way.
Why are the wrong answers always among the options?
Because the examiners know which order children use. A left-to-right answer, and a divide-before-multiply answer, are both predictable, so both get printed. That is worth knowing: finding your answer among the options is not evidence that it is right. On this topic it is almost evidence of nothing at all.
How should my child set these out?
Number every operation above the calculation before touching any of it, then do one operation per line, rewriting the whole calculation each time. The extra line takes about three seconds; the mistake takes the mark. The temptation under time pressure is to do two steps in the head at once, and that is precisely when the order slips.
Does estimating help here?
Considerably, in multiple choice. A rough estimate before calculating usually eliminates two options in a couple of seconds, and it also catches the wrong-order answer, which is often wildly different in size rather than slightly off. Estimate, then calculate, then check the two against each other.
Sources
- GL Assessment — 11+ familiarisation materials and question type descriptions Published 2025.
- Clever Clogs Academy — our own Year 4 and Year 5 lesson records, Winslow Published September 2025 to July 2026.
We are not affiliated with, endorsed by or connected to GL Assessment or Buckinghamshire Council. Test arrangements change; always check the council's own pages for the current year's dates.
We Teach This Method Every Week in Winslow
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