Significant Figures 1 All nonzero numbers count123 2

Significant Figures 1) All non-zero numbers count(123) 2) Leading zeros never count(0. 001) 3) Captured zeros always count(1003) 4) Trailing zeros count only if a decimal is present(100 or 100. )

Significant Figures • Atlantic-Pacific Rule 0. 300 203. 00 100

Significant Figures Rules for Calculations Exact Numbers Addition/Subtraction Multiplication/Division

Exact Numbers • Exact numbers never figure in to significant digits in calculations. They have an infinite number of significant figures. • Examples of exact numbers are……….

Exact Numbers • Conversion factors or mathematical definitions. • 1 kg=1000 g • 1 in=2. 54 cm • 1 cm=. 01 m

Exact Numbers • Counting Numbers • • 3 students 45 cars 675 diplomas 25 points that Texas scored.

Exact Numbers • Formula numbers • Numbers associated with formulas • 4/3 pr 2

Multiplication & Division • Your answer must have the same amount of significant figures as the number in your problem with the least number of significant figures. • 2. 34 x 2. 587 = (6. 05358) so 6. 05 (3 s. f. ) – 2. 34 has 3 s. f. and 2. 587 has 4 s. f. – Answer can have only 3 s. f.

Addition & Subtraction • Your answer must have the same amount of decimal as the number in your problem with the least number of decimal places. 4. 78+17. 1+. 345= 17. 445 4. 78 2 d. p. 17. 1 1 d. p. . 345 3 d. p So our answer can only have 1 decimal place, Therefore 17. 445 must be changed to 17. 4