Number puzzle

ZEHN

“One number. One target. Order decides.”

DREH’s twin, with numbers instead of words: a starting number, a target number, a handful of maths cards – and real maths along the way.

× 7 √ x² ÷ %

How it works

From starting number to target

Look at the target

The target number is at the top, your starting number below it, and a few maths cards in between.
Do the maths

Each card calculates: plus 3, times 2, square root, reverse the digits. Each card only as often as it allows.
Find the order

Doubling and then adding 3 is not the same as the other way round. Match the best solution’s move count for three stars.

At a glance

A course through maths: plus and minus, times and divide, squares and roots, powers, fractions, percentages, logarithms and trigonometry. The last five worlds mix it all.
29 maths cards plus 11 cards from DREH that work on digits: 120 reversed is 21.
Exact maths: every number is a reduced fraction, never a rounded decimal. If a result does not work out, the card tells you why.
The same 1,200 levels in English and in German, with measured, steadily rising difficulty.
Easy or Hard, twelve designs and six music tracks – just like DREH.

Worlds