# Rising Tide

A ladder hangs over the side of a ship anchored in a port. The bottom rung touches the water. The distance between rungs is 20 cm and the length of the ladder is 180 cm. The tide is rising at the rate of 15 cm each hour.
When will the water reach the seventh rung from the top?

### 12 guesses to Rising Tide

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• Chris

Wont the boat just float up when the tide gets higher bringing the ladder up with it? so never?

• You’re right, Chris!

The boat will rise with the tide, so the ladder rungs will remain the same.

You’re today’s winner!!!

• Scottina

Ship rises

• Crow

Never, if the tide is rising, then the ship will be rising too, regardless of how much it rises per hour.

• christine doyle

Never. If the tide is rising, then it is raising the ship water too. So water will only reach the first rung.

• Dude 2

The boat will rise with the tide even if its anchored???

• junsy

Never. If the tide is raising water, then it is raising the ship on water, too. So water will never reach higher than it currently is.

• The ship is rising so the seventh rung is never reached.

• Wolfyy

Never. Since the ladder is attached to the boat it will rise when the boat rises along with the tide. Thus, no matter how long you wait the water will never cover seven rungs unless the ship is to sink.

• Ayden Isbirian

2 and 2/3 hours

• Earl Sanders

Seems like a trick question. If the boat is anchored, it shouldn’t rise with the tide. Then the answer is about 9 hours