Fast Calculation Strategies
Numerical reasoning tests are timed. Working faster without sacrificing accuracy can mean the difference between finishing and running out of time. Here are strategies to speed up your calculations.
1. Percentage Shortcuts
- 10% = divide by 10. 10% of 450 = 45.
- 5% = half of 10%. 5% of 450 = 22.5.
- 20% = double 10%. 20% of 450 = 90.
- 15% = 10% + 5%. 15% of 450 = 45 + 22.5 = 67.5.
- 25% = divide by 4. 25% of 400 = 100.
2. Multiplication Shortcuts
- × 10 = add a zero (or move decimal).
- × 5 = × 10 ÷ 2. 48 × 5 = 240.
- × 25 = × 100 ÷ 4. 48 × 25 = 1200.
- × 11 = × 10 + original. 23 × 11 = 230 + 23 = 253.
3. Estimation First
When answer options are far apart, estimate before calculating precisely. 47 × 23 ≈ 50 × 20 = 1000. If options are 800, 950, 1081, 1200, you can often eliminate 800 and 1200 without full calculation.
4. Avoid Unnecessary Steps
- Don't convert to decimals if fractions work. 3/4 × 80 = 60 is faster than 0.75 × 80.
- Use the calculator efficiently. Know which operations you need before you start typing.
5. Practise Under Timed Conditions
Speed improves with practice. Do timed practice tests regularly. Track your time per question and aim to reduce it while maintaining accuracy.
Use numerical reasoning practice and the numerical reasoning test to apply these strategies.
Frequently Asked Questions
Should I prioritise speed or accuracy?
Accuracy first. A few correct answers beat many wrong ones. But with practice, you can improve both. Aim for speed that doesn't compromise accuracy.
How long does it take to see improvement?
A few weeks of regular practice (2–3 sessions per week) can noticeably improve speed. Focus on the operations that appear most in your target test.
What if I'm naturally slow at maths?
Shortcuts and estimation can help. Focus on the most common question types. Practice builds both speed and confidence. Many people improve significantly with preparation.