Professor Layton and the Diabolical Box

Puzzle 090: The Unusual Fountain

Original diagram for Puzzle 090: The Unusual Fountain

A fountain spells out people's ages with its spouts, but one spout is never needed, so which one?

Chapter
Chapter 6
Location
Fountain
Picarats
20 picarats
Type
Circle Answer
Region
Same in all versions
Hint 1: A gentle nudge. Tap to flip.
Hint 1

Work out what number each spout stands for.

Tap to flip back
Hint 2: The key idea. Unlocks after the previous card is flipped.
Hint 2

The middle spout counts tens. The lettered spouts count ones.

Tap to flip back
Hint 3: Almost there. Unlocks after the previous card is flipped.
Hint 3

How many single-digit spouts do you actually need?

Tap to flip back
Answer: See the answer. Unlocks after the previous card is flipped.
Answer

The answer is spout J.

Tap to flip back
Solution, FAQ and sources

Solution

The middle spout stands for 10, and spouts A to I stand for 1 to 9. That covers every age: tens from the middle spout, then up to nine more from A to I.

There's never a reason to fire a tenth single spout, so **spout J** is useless.

About this puzzle

A fountain shows the age of anyone who walks up by firing its spouts in sequence. A five-year-old gets spouts A to E, a 15-year-old gets the middle spout and then A to E, and a 30-year-old gets the middle spout three times. One spout is completely useless. Which?

Unofficial fan guide, not affiliated with LEVEL-5 or Nintendo. Puzzle description, hints and solution written by Hint by Hint.

Similar puzzles: Puzzle 044: Tangled Ropes, Puzzle 027: A Dramatic Farewell, Puzzle 074: PU!, Puzzle 072: Scrambled Photos

All Professor Layton and the Diabolical Box puzzles

FAQ

What is the answer to Puzzle 090, The Unusual Fountain, in Professor Layton and the Diabolical Box?

The answer is spout J.

Where do you find Puzzle 090 in Diabolical Box?

Puzzle 090 appears in Chapter 6, in the Fountain area.

How many picarats is Diabolical Box Puzzle 090 worth?

20 picarats.

Sources

Facts checked on November 14, 2026

Unofficial fan guide. Not affiliated with, endorsed by, or sponsored by LEVEL-5 Inc. Professor Layton, The New World of Steam, and all related names, characters, and trademarks are the property of their respective owners.