Math Mingle: Brain Puzzles

A maths puzzle that tricks you into doing hundreds of calculations without noticing you are doing them.

Here are five numbers. Exactly two of them add up to a third. Tap those two.

That is the whole rule, and it is the kind of rule that does not stay easy. To find the one pair you have to check the others — and checking pairs is addition, done in your head, over and over, faster each time. A single pentagon board asks for around a hundred of them. You will not count them. You will be too busy looking.

HOW A ROUND GOES

Solve each group and it collapses into one big shape carrying its answer. When every group is done, those answers form one last puzzle in the same places — and finding a pair there ends the round. Watching the second puzzle assemble itself out of the first is the moment the whole thing clicks.

THE CLOCK IS THE SCORE

The timer starts when the board appears and is recorded to the millisecond. A wrong tap does not end anything and costs you no lives — it adds seconds. Speed and care are the same currency here, which is what makes a clean run worth something.

FOR A SEVEN-YEAR-OLD AND FOR YOU

EASY is single digits, which a child who knows their number bonds can play on the first try. EXPERT runs to ninety-nine and to the twenty times table. Same rule, same screen, nothing new to learn on the way up.

• Three boards — Triangle (3 groups of 3), Square (4 of 4), Pentagon (5 of 5) • Five kinds of maths — add, subtract, multiply, divide, or a mix of all four • Four difficulties — Easy, Medium, Hard, Expert • Sixty leaderboards, one for every combination, ten best times each • Eight themes, light and dark, including a blackboard and a blueprint • Every puzzle is generated and verified: exactly one answer per group and exactly one in the final group, always • No ads. No purchases. No account. No internet permission at all. • Plays the same on a phone and a tablet — every feature on every device