6

123456
Across
  1. 2. - A symbol representing an unknown value.
  2. 3. Value - The distance of a number from zero, regardless of direction.
  3. 5. - The likelihood of an event happening, expressed as a ratio.
  4. 6. - The result of adding numbers together.
Down
  1. 1. - The product of all positive integers up to a given number, denoted by "!".
  2. 4. - The branch of math dealing with basic operations like addition, subtraction, multiplication, and division.