Significant Figures

• Non-zero digits are always significant.
• Zeros between nonzero digits are always significant.
• These are digits that are either certain, uncertain or estimated.

  Significant Figures
• Zeros within a whole number are not significant unless there is a nonzero digit ahead of it.

  e.g. 340,000 = 2

  204,000 = 3

  505,500 = 4

  111,111,000 = 6
• Trailing zeros, which are zeros at the end of the number, are significant if and only if there is a decimal point present in the number or they carry overbars.
• In calculations involving addition/subtraction, round off all answers to one more decimal place than the least precise measurement used in the calculation.
• In calculations involving multiplication/division, the final answer must be based on the least number of significant digits on the given numbers.
• Zeros are not significant if they act as placeholders.