Mixed speed challenge — Speed Calculation

The fast method

Spot the trick — “look at the numbers first, then use the quickest method”

1. A 7, 8 or 9 in the ones place → round and fix.
2. × 4, 8, 5, 50 or 15 → doubling or halving tricks.
3. ÷ 5, 25 or 50 → double first. A percentage → start from 10%.
4. Checking or estimating → nines or rounding.

Use it for: Speed maths competitions, olympiad mental rounds, and timed tests in school.

Worked example: 84 × 15 = 1260

✏️ Practice

Work it out in your head or on paper, then tap your answer — or type it and press Check. Stuck? Press “Show me how”.

🏁 Lesson 15 test

20 questions. Check each answer, then go to the next one. Get 16 or more right to pass — and beat the clock: finish within 4 min.

🏅 Sign in with Google to earn the 🏆 Speed Champion badge when you pass — and a certificate when you finish all 5 lessons of Part 3 · Speed dividing, percentages and checking. You can still take the test without signing in.

🖨️ Speed Maths Test Worksheet

• Worksheet set 1 (PDF)
• Worksheet set 2 (PDF)
• Worksheet set 3 (PDF)