Module overview
What the test trains
This module focuses on mental calculation speed, arithmetic fluency, concentration and work rate. It is designed to make the underlying process easier to recognise, repeat and review before you add more speed or workload.
Task profile
What the task looks like
What it involves
- Complete basic addition, subtraction, multiplication and division problems.
- Work mentally without relying on slow written-style algorithms.
- Maintain a steady rhythm across a timed or question-limited run.
- Use estimation to catch impossible answers before submitting.
Practice screen example
These screenshots show CBAT Academy’s independent practice version of the task.
A quick method for mixed arithmetic
For 27 × 6 + 8, keep the calculation in two clean parts: 27 × 6 = 162, then 162 + 8 = 170. A rough check—30 × 6 is 180—confirms that 170 is in the right range.
- Read the operation signs before committing to the numbers.
- Complete multiplication or division first when the expression contains another operation.
- Run a brief scale check, type the answer, press Enter and reset immediately for the next item.
The trainer records both work rate and accuracy. A steady solve–check–enter rhythm is more useful than answering in bursts and then losing time to avoidable corrections.
Learn by doing
Mental arithmetic: choose a method you can check
These original arithmetic examples teach three ways to reduce mental workload. Solve each one before revealing the method. The aim is a correct, repeatable calculation, followed by a short check before entering the answer.
1. Subtract using a nearby round number
Calculate 403 − 187 mentally.
Show answer and method
- Replace 187 with 200 for the first step: 403 − 200 = 203.
- You subtracted 13 too much, so add 13 back.
- 203 + 13 = 216. Check: 187 + 216 = 403.
216.
Watch out: 203 − 13 = 190 adjusts in the wrong direction. Subtracting a larger number first makes the result too small.
2. Split a multiplication
Calculate 48 × 7 without writing a column multiplication.
Show answer and method
- Use 48 = 50 − 2.
- 50 × 7 = 350, and 2 × 7 = 14.
- 350 − 14 = 336. The result should be just below 350.
336.
Watch out: 348 comes from subtracting 2 instead of 2 × 7. Apply the multiplier to both parts.
3. Divide by reversing multiplication
Calculate 156 ÷ 12.
Show answer and method
- 12 × 10 = 120, leaving 36.
- 12 × 3 = 36, so the quotient is 10 + 3.
- Check the complete answer: 13 × 12 = 156.
13.
Watch out: A remainder of 36 is not 36 extra groups. Divide the remainder by 12 before adding it to the quotient.
A short drill before you start
Practise each operation separately, then mix them. After a short block, record correct answers and attempts as well as time. If faster entry causes more sign or place-value errors, return to the same difficulty and repair that error before increasing pace.
Try free Numerical Operations practice →Build the next skill
Original CBAT Academy training examples. These are not official RAF questions.
Interface briefing
Controls and difficulty
Controls
Calculate the answer to each problem and type it directly into the on-screen numeric field — there is no multiple-choice list.
Difficulty and settings
The time budget is fixed at 90 seconds for every difficulty; only the question count changes, from 20 at Easy to 40 at Hard, so higher difficulty is almost entirely a work-rate increase.
Read how practice scores and estimates work →Training plan
Build a method that holds up under pressure
Why this becomes difficult
- Simple problems create pressure to rush and mis-key answers.
- Slow written-style algorithms consume too much mental time.
- One difficult multiplication or division can stall the response rhythm.
- Fatigue increases sign, place-value and transposition errors.
Preparation tips
- Memorise multiplication facts through at least 12 × 12.
- Use decomposition, such as 47 + 38 = 47 + 40 − 2.
- Estimate before committing so impossible answers stand out.
- Keep a steady response rhythm instead of bursts followed by long pauses.
- For subtraction, use counting-up when it is faster than borrowing.
Common mistakes
- Treating addition and subtraction signs as interchangeable under speed.
- Overcomplicating easy calculations.
- Continuing to check an answer after submission.
- Losing place value when entering multi-digit answers.
- Letting one poor question affect the next several.
Useful practice drills
- One-minute blocks of each operation, followed by mixed-operation blocks.
- Rapid multiplication and division fact recall.
- Mental complements to 10, 100 and 1000.
- Estimate-first drills that reject obviously impossible answers.
Transparency
Sources and information status
Task guidance on this page describes CBAT Academy’s own software. Broad aptitude context is checked against the public references in the source register.
This guide describes CBAT Academy’s independently developed practice modules. It is not an exact specification of any current RAF, Canadian Forces or Ministry of Defence assessment. Official content, timings, scoring and administration may differ.
Continue the briefing
Turn the method into repeatable performance.
Launch the interactive trainer, begin with accuracy and review the pattern behind each mistake before increasing pace.