Arithmetic quiz

More questions about Arithmetic

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

1. 1 Easy

   What is the decimal equivalent of the fraction $\frac{1}{8}$?

   Answer: 0.125

   Why: Wall Street's eighths came from the Spanish dollar's 'pieces of eight', so until 1997 the smallest NYSE price step was 12.5 cents.

2. 2 Medium

   Which property allows regrouping numbers without changing the sum?

   Answer: Associative property

   Why: The associative property changes how terms are grouped with parentheses, whereas the commutative property changes their order.

3. 3 Hard

   What composite passes Fermat's test for all coprime bases?

   Answer: Carmichael number

   Why: A composite number qualifies as Carmichael only when it has no squared prime factors and every $p - 1$ divides $n - 1$.

4. 4 Easy

   Which ancient counting frame uses beads on rods?

   Answer: Abacus

   Why: The pebbles used on early counting boards were called calculi, which gave English the word calculate.

5. 5 Medium

   Which value is the smallest odd prime number?

   Answer: 3

   Why: Only two and three escape the six pattern: every other prime sits exactly one step above or below a multiple of six.

6. 6 Hard

   Which prime factors make a fraction terminate in base 10?

   Answer: 2 and 5

   Why: Because ten factors into two and five, only denominators with those prime factors can scale into powers of ten.