TED-Ed: Can you solve the fortress riddle? | Henri Picciotto

The kingdom is under threat from neighboring states that aim to breach its walls using siege weapons. The kingdom must determine the optimal wall segment size that cannot be destroyed by any combination of enemy wall busters. The Sieve of Eratosthenes, a method for identifying prime numbers, is adapted to solve this problem efficiently. By eliminating vulnerable wall sizes, the kingdom identifies 43 meters as the optimal wall segment length, ensuring its defense against the siege.

What is the primary threat to the kingdom's tiny Dino creatures?

• Natural disasters

• Economic collapse

• Internal rebellion

• Neighboring states

What sizes do the wall busters from rival kingdoms come in?

• 8, 16, and 24 meters

• 6, 9, and 20 meters

• 5, 10, and 15 meters

• 7, 14, and 21 meters

Which ancient technique is used to solve the wall problem?

• Pythagorean Theorem

• Euclidean Algorithm

• Archimedes' Principle

• Sieve of Eratosthenes

What is the purpose of using the Sieve of Eratosthenes in the context of the wall problem?

• To identify prime numbers for wall lengths

• To determine the cost of wall segments

• To calculate the speed of wall construction

• To eliminate numbers that can be formed by wall busters

What is the largest wall segment length that cannot be destroyed by any combination of wall busters?

• 44 meters

• 43 meters

• 42 meters

• 41 meters

How does the kingdom plan to use the identified wall segment length?

• To create a new road

• To reinforce the kingdom's defenses

• To construct a bridge

• To build a new castle

What is the outcome for the kingdom after using the optimal wall segment?

• The kingdom falls to the invaders

• The kingdom relocates to a safer area

• The kingdom remains safe and secure

• The kingdom's defenses are breached