Aon numerical reasoning: check the test before you practise
Aon's Scales Numerical assessment gives you a data sheet and a series of statements, and you decide whether each one is true, false or cannot be answered from that sheet. This guide explains what the task asks, what its twelve-minute limit does not mean, and works one statement you can judge yourself.
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In Scales Numerical, Aon’s numerical reasoning test, the arithmetic is only half the work. You get sheets of figures and a series of statements about them, and you decide whether each statement is true, false, or impossible to answer from the sheet in front of you. Getting the sum right is not the same as settling the claim, and settling claims is what most of this page is about.
Aon runs two other tests that work with numbers, Scales EQL and DigitChallenge. Both are mental arithmetic and nothing else. If your invitation names one of those, go straight to the untimed drills in our numerical section.
Preparing for Scales Numerical works in two layers. Learn the decision format from Aon, because only Aon’s own material shows you that. Then fix whichever calculations slow you down, starting with the one further down this page.
Which Aon numerical test are you taking?
Aon’s preparation pages list each test with what it measures and how long it runs. These are the three that work with numbers. Aon styles the names in lower case on its own site, so “scales numerical” on your invitation is the test this page calls Scales Numerical.
| Test | What it asks, and the published time |
|---|---|
| Scales Numerical | Judge a statement against supplied numerical data. 12 minutes, 37 tasks. |
| Scales EQL | Basic arithmetic by mental calculation. 5 minutes. |
| DigitChallenge | Basic arithmetic by mental calculation. 6 minutes. |
If your invitation does not name the test, check the instructions that came with it, or ask the organisation that sent it. Aon lists many tests beyond these three, so guessing from the employer’s name is not a safe way to choose what to practise.
Thirty-seven tasks in twelve minutes is not a per-question deadline
That pairing looks like a stopwatch to train against. Aon’s own practice document says otherwise:
The actual assessment you will take is timed, but you are not expected to answer all the questions … work quickly and accurately, to try to get as many correct as possible in the time provided.
That is Aon’s wording, from page 2 of the practice tasks linked below, with the emphasis added here.
The arithmetic is worth seeing: 37 tasks in 12 minutes works out at more than 3 a minute. That describes the whole assessment rather than setting a target for any one task. Aon asks for speed and accuracy together, and says you are not expected to finish.
So do not rehearse against a per-question limit Aon has not set. Rehearse accurate decisions against the overall time, and get as many right as you can inside it.
A correct calculation can still lead to CANNOT SAY
Aon publishes a practice document for Scales Numerical, and its instruction page describes the task. You get data sheets carrying information in numerical form, and a series of statements. Your job is to judge each statement against those sheets.
Every statement carries three answer options: TRUE, FALSE and CANNOT SAY, and one of them is correct. The third option is the one that changes how you work. Getting the sum right does not settle a statement. What settles it is whether the sheet in front of you establishes the claim.
A sheet of monthly order counts can settle a claim about how far the orders moved. It cannot settle a claim about why they moved, however likely the reason sounds, because counts carry no causes. Calculating a number and proving a statement are different jobs, and the second one is being marked.
The same document adds that each statement relates to one data sheet only, and that you have to find that sheet and refer to it. So your first move is not arithmetic: find the sheet the statement is about, then read it.
Aon also tells candidates to have pen, paper and a calculator ready before starting. Do the same when you practise, so you rehearse the whole workflow instead of doing sums in your head.
The official exercises are at Aon’s numerical reasoning practice tasks. That is where you learn the format, and this page does not replace it.
Judge one statement for yourself
Here is a sheet and a statement to judge, set out the way Scales Numerical does it. We wrote the question, and the answer labels are ours.
Judge this statement
| Month | Orders |
|---|---|
| March | 250 |
| April | 320 |
Orders rose by more than a quarter.
Independent practice written for Testonome, not Aon material. Nothing here is recorded or scored.
Check your answer
B, True. The orders rose by 320 − 250 = 70. Measured against March, where they started, that is 70 ÷ 250 = 0.28, or 28%. A quarter is 25%, so the rise clears it and the statement holds.
The other two answers each come from one identifiable move.
- You measured the rise against April. That gives 70 ÷ 320, or 21.9%, which is under a quarter, and the statement then looks false. Here the wrong base changes the verdict as well as the number.
- You decided the sheet could not settle it. Not enough data is the right answer when the sheet lacks what the claim needs, such as why the orders rose. This sheet carries both months, so the size of the rise is something you can check.
One slip in the arithmetic flipped the verdict there. That is the case for drilling the calculation on its own: the better you know the method, the less of your attention it takes when the decision needs it. The drills are free here on Testonome, with no payment and no account to create.
What to practise next
One statement can expose a mistake. It cannot show you are ready.
| Your answer | What to do next |
|---|---|
| B, and you can say why the base is March | Build consistency on the untimed drills below, then work through the statements in Aon’s practice document. |
| B, but you picked it without working it out | Do not count it. Read the working above, then judge a statement you have not seen. |
| A | Fix the base first. You judged the statement soundly against a figure that was wrong. |
| C | Re-read what the sheet carried. Both months were on it, so the rise was measurable. |
| You were unsure which way to go | Say out loud what the sheet would have to show for the statement to hold, then check whether it does. That is the whole task. |
For Scales Numerical, that adds up to a plan:
- Learn the TRUE, FALSE and CANNOT SAY format from Aon’s own familiarisation material.
- Notice which calculations make you stop and think.
- Drill those separately here on Testonome, until the method is automatic.
- Go back to Aon’s practice tasks and work accurately against the published time.
Percentage change is one of those calculations, and the one this page has just put in front of you. If choosing March as the base was not automatic, fix that before you add any time pressure. The button below opens the percentage-change skill page, which sets out the method in full and starts a free untimed drill of five original questions, each with the kind of explanation you have just read. That page also suggests a target time for the calculation. It is our own pacing guide for that one skill, and it is not an Aon figure: Aon publishes no per-question limit for Scales Numerical, which is the whole point of the section above.