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Scales and coin slot
Published October 16, 2026.
Two mechanisms play with values: the scales, where you must balance the pans, and the coin slot, where you must reach a sum. In both, the plates give the values.
The scales: weights are deduced
The weight of each shape is written on a plate, sometimes indirectly: as equalities between shapes (« two circles weigh as much as a square »). Write the equalities down first, then deduce the value of each shape, as in a small system of equations: starting from the shape whose weight you know, you find the others one by one.
Put weights on the pans, then pull the pin to weigh. The pin is an attempt: pulling it « to see » is a 15-second mistake if the scales are not balanced. So do the calculation first: the sum of the weights on each side must be equal, and several combinations may work.
The number of weights
Scales never use more weights than the plates describe. Start with the shapes whose value is certain, and do not put anything on the pans before you have done the calculation.
The coin slot: the exact sum
Slide coins into the slot to reach the wanted sum, then use the lever, which is an attempt. The slot shows the sum already slid in, except when values are deduced from a legend: then each coin carries a symbol, and the count is done in your head.
Coin values are written in ordinary digits in the centre, in large type, the size being just one more landmark.
An example of reasoning
Imagine a plate that says « two circles weigh as much as a square » and another that gives the weight of the circle. The weight of the square follows at once, and a third equality will let you find the triangle. You always proceed the same way: start from the shape whose value is given, then climb up each equality. Once every value is known, the scales are only a matter of addition: you look for a split of the available weights that gives the same sum on each side.
Do not be guided by the size or look of a shape: only the plate is authoritative.
Practise in the game
The game's tutorials, with no clock and no penalty, let you practise this subject: