➕ Algebra 1 · Exponents and Polynomials

Scientific Notation cheat sheet

Everything you need on one page. Print it, or switch on test-yourself mode to blur the answers and check your memory.

The form

  • a × 10n with 1 ≤ a < 10 and n an integer
  • Positive numbers: 10 or more has a positive exponent; between 0 and 1 has a negative exponent.
  • From 1 up to (but not including) 10: exponent 0

Converting

  • Slide the point until one nonzero digit is on its left
  • Count the slides, not the zeros
  • Back to ordinary form: positive exponent slides right, negative slides left

Operations

  • Multiply: fronts times fronts, exponents add
  • Divide: fronts divided, exponents subtract
  • Add or subtract: match the powers first, keep the power
  • Then fix the front number
  • Compare: the bigger exponent wins, then the front numbers (positive numbers in scientific notation)

Real sizes (all about)

  • Speed of light: about 3.0 × 108 meters per second
  • Sun to Earth: about 1.5 × 108 kilometers
  • Human hair width: about 1 × 10−4 meters
  • Kilo is 103 and milli is 10−3

Traps

  • 45 × 103 is not in scientific notation
  • 3.2E5 on a calculator means 3.2 × 105
  • Do not add exponents when adding

Formulas

  • Scientific notation: a × 10n with 1 ≤ a < 10 and n an integer
  • Multiply: (a × 10m)(b × 10n) = (a × b) × 10m+n
  • Divide: (a × 10m) ÷ (b × 10n) = (a ÷ b) × 10m−n
  • Add: a × 10n + b × 10n = (a + b) × 10n (same exponent)
  • Subtract: a × 10n − b × 10n = (a − b) × 10n (same exponent)
  • How many times as large: (larger number) ÷ (smaller number)

Scientific Notation cheat sheet from HighSchoolQ.com, for personal study use.