In Rectangles & Primes, your goal is to build rectangles with a given number of cells. The target number of cells is written on the blackboard. A rectangle is built from at least two pieces and all pieces must have the same length.

On the bottom left you find two icons to start playing. One is for the training mode, where there is no time limit and you can just practice your rectangle skills. The other one is for a game against the clock. Try to gain as many diamonds as possible within the time limit. Maybe you'll achieve a new high score!

Gaining diamonds

If you think that you've built a matching rectangle, you can click on the CHECK button to check your result. If you got it right, you receive as many diamonds as your rectangle is high. If your rectangle does not match the number, you lose 5 diamonds.

A special case is the SQUARE: If your rectangle is as high as it is wide, you receive 10 diamonds.

Prime numbers

Sometimes there's a number that cannot be built as a rectangle. These are called PRIME NUMBERS. You have to click the PRIME button to classify them as primes. This is very tricky, so finding a prime will give you 20 diamonds. But watch out: Calling a number a prime that is actually not a prime will lose 10 diamonds.

If you're not sure what to do with a number, you can always SKIP it. This will cost you 2 diamonds.,