Online math game

Balance: level the scale with one weight

Also known as: balance the scale, balance scale math puzzles, number balance, which weight balances the scale

The left pan holds weights with numbers, the right pan holds a few weights and an empty spot. Pick the weight that makes the pans level. A round lasts a minute and a half, and you can play 10 minutes a day without signing up.

Go to the game ↓
  • 1.5 minutesper round
  • 4 levelsup to two unknowns
  • No sign-up10 minutes a day
  • Progress30-day chart
What it trains

Why balance a scale

Every puzzle is an equation written in weights: 6 and 9 on the left, 5 and an empty spot on the right, so you need a weight of 10. You add up one pan, subtract the known weights from the other and keep the order straight. At later levels the weights show products, and there are two unknown weights.

After you answer, the weight lands on the pan and the scale shows the result: level, too heavy or too light. Once you sign up, your account shows your score, correct answers, mistakes and top level.

  • You mix up what to subtract from whatThe scale shows which pan is short
  • Your child is getting ready for equationsA visual equality instead of the letter x
  • You want to do more than column arithmeticAddition, subtraction and multiplication in one puzzle
  • You need a short math taskA minute and a half per round

Mental math

Addition, subtraction and the times tables.

Understanding equality

Both pans must weigh the same.

Working memory

Keep the total of one pan in mind while you work out the other.

Logic

Two identical unknown weights mean dividing in half.

Rules

How to play

  1. Start

    Press “Start”. A scale appears: weights on the left pan, and weights plus an empty spot with a question mark on the right. The heavier pan sits lower.

  2. Calculate

    Add up the weights on the left pan and subtract the ones already on the right. The difference is the weight you need.

  3. Answer

    Tap one of the weights at the bottom or press keys 1–4. The weight lands on the pan, and the scale shows the result.

  4. Mistake

    If the pans don’t level, we highlight the right weight and show the balanced scale.

  5. Level

    Three correct answers in a row take you up a level, and a mistake takes you down. A correct answer earns as many points as your current level.

Play online

Balance online

Level the scale with one weight. Without sign-up you get 10 minutes of play a day.

Balance

The left pan holds numbered weights; the right pan has weights and an empty spot. Pick the weight that balances the scale.

Free play left today without signing up: 10 min

Method

What the exercise is based on

A balance scale is a familiar school model of equality: whatever is on one pan has to be matched by the other. It’s a way to prepare for equations without calling them that. The wrong options are based on common mistakes: one or ten more or less, a sum without the subtraction, a doubled answer instead of half.

If you’d like logic without numbers, try “Scales”: you weigh items to find the heaviest one. Quick checking of math problems is in “True or False”.

1–2SumsOne weight up to 10, then several weights up to 50
3MultiplicationThe weights show products: 2×7 weighs 14
4Two unknownsTwo identical weights; find the weight of each
Who it’s for

Which ages

Adults

A minute and a half of mental math with a visual result.

Kids

Suitable from age 6: for kids there are only the first two levels, sums up to 50 and three answer options.

60+

No penalties for mistakes: a wrong weight only lowers the level, and the scale shows right away what went wrong.

Program finder

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Answer 4 questions and we’ll put together a daily program of 5 trainers. We’ll email you the full 2-week plan.

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Questions

Frequently asked questions

What does a “2×7” weight mean?

It weighs whatever the multiplication gives: 14. These weights appear from level 3.

How do I solve a puzzle with two question marks?

Both unknown weights are the same. Subtract the known weights on the right from the left pan and divide what’s left in half.

Do mistakes cost points?

No. A mistake lowers the level by one, and the points from earlier answers stay.

Do I need to sign up?

No, you can play 10 minutes a day right away. Free sign-up lets you keep playing, save your results, track your progress and unlock the daily workout.

Does it work on a phone?

Yes, the game runs in the browser on a phone, tablet or computer. There’s nothing to install.

Save your results and track your progress

Free sign-up: round history, a chart by skill and a daily workout of 5 exercises. No credit card needed.

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