Four Jams (Jam Weight in the UK version) is a puzzle in Professor Layton and the Unwound Future.


US Version

Four types of jams are combined into pairs and placed in the four boxes below.

Use the scale to determine the relative weights of each type of jam, and label them from lightest to heaviest, 1 to 4.

UK Version

You have eight jars of jam of four different types, depicted by the different colours. The different types of jam vary in weight. Your jars have been put into boxes in pairs.

Use the scales to work out the relative weights of each type of jam and rank them 1 to 4, with 1 being the lightest and 4 the heaviest.


Click a Tab to reveal the Hint.

Identify the boxes that share a jam with each otehr. By weighing these boxes together, you can compare the weight of the two jams that aren't the same.

Try comparing the red/blue with the red/green box. You should be able to identify whether the blue jam is heavier than the green jam or vice versa.

Continuing on from Hint Two, try to figure out the weight of the red jam.

To do so, compare the red/green box with the blue/green box. You should find that blue > green > red.

Thinking of red, green, and blue as 1, 2, and 3 temporarily (lightest to heaviest), you'll find that the yellow/yellow box and the blue/green box are equal in weight. This means that the two yellow jams equal 3 + 2 (the relative weights of the blue and green jams).

In other words, one yellow jam has a weight of 2.5. If you fit that into what you know about the rest, you're done!



Too bad!

You need to be methodical in how you weigh the jars of jam.


US Version


Blue > Yellow > Green > Red

Comparing the red/blue box with the red/green shows that blue > green.

Comparing the red/blue box with the blue/green box shows that green > red.

And finding that the yellow/yellow box is equal to the blue/green box tells you that yellow is between blue and green!

UK Version

Well done!

Starting with the heaviest, the order is: blue, yellow, green, red.

By weighing the red-blue box with the red-green box, you can work out that blue jam is heavier than green jam. Weighing red-blue with blue-green tells you that green jam is heavier than red jam. Finally, by ascertaining that yellow-yellow is the same weight as blue-green, you can work out that the weight of yellow jam is between that of blue jam and green jam.


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