# Menu » Arithmetic

Please choose the topic you want information about.

- Numbers
- Roman, binary, octal and Babylonian numerals
- Rounding off and significant digits
- Divisor, divisbile and multiple
- Even and odd
- Basic rules / Calculation order
- What is stream-of-consciousness notation (knitting)?
- Ratios
- Fractions
- Percentages
- Negative numbers & greater than (>) and less than (<)
- Sum, difference, product and quotient
- What are powers?
- Long division
- Rules of thumb (to use with estimations)
- Converting units
- Units of time
- Scientific notation (Standard form)
- (Square) Roots
- Simplifying square roots
- Prime numbers
- Number systems (sets)
- Imperial and US units
- Computer memory
- Astronomical measurements