A quick mental math workout
Mental arithmetic is a skill that fades without use and comes back quickly with practice. This one-minute sprint keeps it simple: a sum appears, you type the answer, and the next one arrives the moment you are right.
Choose Easy for addition and subtraction, Medium to add times tables, or Hard for division and bigger numbers. Use the big number pad on a phone or your keyboard on a computer, and try to beat your best score every day.
Quick tricks for faster mental math
A few simple methods make a big difference in a one-minute sprint:
- Multiply by 9: multiply by 10 and subtract the number. 9 × 7 = 70 − 7 = 63.
- Multiply by 11 (two-digit numbers): add the two digits and put the result in the middle. 11 × 36: 3 + 6 = 9, so 396. If the sum is 10 or more, carry the 1.
- Multiply by 5: multiply by 10 and halve it. 5 × 14 = 140 ÷ 2 = 70.
- Subtract by counting up: for 83 − 47, count from 47 to 50 (3) and from 50 to 83 (33), so 36.
- Double and halve: 16 × 25 is the same as 8 × 50, which is 400.
Why practice mental arithmetic?
Doing sums in your head is useful every day, from checking a bill to estimating time and prices. Like any skill, it gets faster with short, regular practice, and it keeps your working memory busy in a fun way. Because the game gives you instant feedback and a clear score, it is easy to see yourself improve from one day to the next.
Choosing a level
Easy uses addition and subtraction up to 20, which suits children and warm-ups. Medium adds bigger numbers and times tables up to 10. Hard adds division and tables up to 15. Try to beat your best score on one level before moving up. For more number puzzles, try Calcudoku and 2048.
How to play Mental Math
- Pick a level, then tap Start. A 60-second timer begins.
- Type the answer with the number pad or your keyboard. It counts as soon as it is right, with no need to press Enter.
- A wrong answer shakes the card and clears it so you can try again. Skip moves to a new sum but breaks your streak.
- Easy uses addition and subtraction, Medium adds times tables, and Hard adds division and bigger numbers.
- Your score is the number of correct answers. Your best score for each level is saved.
Mental Math tips
Add from the left
For 47 + 36, add the tens first (70), then the ones (13), then combine (83). It is faster in your head than carrying.
Use round numbers
For 58 + 27, think 60 + 27 − 2. Rounding to the nearest ten and fixing the difference is often quicker.
Know your times tables cold
On Medium and Hard, most time is lost on multiplication. Practicing the 6, 7, 8 and 9 tables pays off fastest.
Turn division into multiplication
For 56 ÷ 7, ask "7 times what makes 56?" Every division here comes out even.
Frequently asked questions
Is this good for adults?
Yes. The Medium and Hard levels are a quick daily workout for adults, and Easy is great for kids learning to add and subtract.
Do I need to press Enter?
No. As soon as the number you typed is correct, the next sum appears. On a keyboard, Enter with an empty answer skips.
What is a good score?
It depends on the level and on practice. Compare with your own best, which is saved for each level, and try to beat it a little every day.
