Mathematics quiz

More questions about Mathematics

These visible examples show the question style. LearnClash turns the full topic into ranked duels and spaced repetition.

1. 1 Easy

   Which number does the Roman numeral V represent?

   Answer: Five

   Why: V is five, but Romans usually wrote four as IIII rather than IV. At the Colosseum, gate 44 is labelled XLIIII.

2. 2 Medium

   Which mathematical object has only one side and one edge?

   Answer: Möbius strip

   Why: A Klein bottle is one-sided too, but it is closed and has no edge at all, so an ant can cross the whole surface without meeting a boundary.

3. 3 Hard

   Russell's Paradox involves a set that contains all sets that do not...

   Answer: Contain themselves

   Why: Russell hit on it in 1901; the same trap is the barber who shaves everyone who does not shave himself, and so cannot shave at all.

4. 4 Easy

   What happens when you attempt to divide any real number by zero?

   Answer: It is undefined

   Why: Multiplying by zero destroys information, making it impossible to reverse the operation through division.

5. 5 Medium

   The name Google is a misspelling of which massive mathematical number?

   Answer: googol

   Why: Milton Sirotta coined the word for his uncle Edward Kasner, and a mistyped domain search in September 1997 landed on google.com instead.

6. 6 Hard

   What is the highest-dimensional normed division algebra that can exist over the real numbers?

   Answer: Octonions

   Why: Hurwitz's theorem proved in 1898 that the only real normed division algebras exist in dimensions 1, 2, 4, and 8.