Counting Significant Figures the Easy Way

                                                                                                Std MISC

 

This brief tutorial allows you to easily remember how to count the number of significant figures in any number:

 

1. Always non-zero numbers count.

2. Never count leading zeroes (zeroes to the left of the first non-zero digit in the number)

3. Sometimes count trailing zeroes (zeroes to the right of the last non-zero digit in the number)

      a. If there is no decimal in the number – DON’T COUNT THEM

      b. If there is a decimal in the number anywhere – DO COUNT THEM

4. Always count zeroes that are not leading zeroes or not trailing zeros

 

 

Examples

 

Rule

Example

# Sig Figs

1

9483112

7

 

 

 

2

0007256

4

 

0.007256

4

 

00.07256

4

 

000.7256

4

 

0007.256

4

 

0007256.

4

3a

7289000

4

3b

7289000.

7

 

0.7289000

7

 

7.289000

7

 

728.9000

7

 

7289.000

7

 

728900.70

8

4

700000008

9

 

50400708002

11

 

50400708

8

 

2000507749

10

 

50400708.

8