What do they do if someone moves in? Comments?

If you counted everyone in Pekin, would you come up with 33,900

Significant Figures or “Sig Figs” 0 1 Whose more important, me or you?

Odometer on your car DO NOT mean a number is important or not DOES indicate the precision of a number Significant Figures or “Sig Figs”

The 1 st calculation of the Everest’s height was done in 1852 by Radhanath Sikdar He calculated --> 29,000 ft He reported --> 29,002 ft. WHY? Latest Measurement is 29,028 ft.

See Sig Fig cards Look at the examples and come up with 3 rules for when a number is significant or not 1.) Any number 1-9 is always significant 2.) 3.) 4.) Come up with 3 more on a piece of paper with your groups name on it to turn in

The Rules 1.) Non-zero numbers are always significant 1, 2, 3, 4, 5, 6, 7, 8, 9 and so is a zero with a line over it (it does not mean repeating in this class) 12 ft 2 sig figs.4512 cL 4 sig figs Examples 32.2 mm 3 sig figs 140 ms 3 sig figs

The Rules 302 s 3 sig figs kL 5 sig figs Examples cm 3 4 sig figs 1,000,000,001  g 10 sig figs 2.) 0’s between Sig Figs are always significant  g 5 sig figs

3.) 0’s to the left of all non-zero numbers are never significant The Rules 0035 mi 2 sig figs g 3 sig figs Examples L 1 sig figs These zeros don’t mean anything These zeros are just place holders

4.) 0’s to the right of all non-zero numbers are only significant if they are to the right of a decimal. ( or if they are between 2 sig figs) The Rules 35,000 in 2 sig figs kg 2 sig figs Examples These zeros are just placeholders s 6 sig figs cm 4 sig figs

The Rules 4 apples Number of people in the class room Examples 5.) Measurements done by counting have infinite Sig Figs (Infinite Precision). So do numbers that are considered perfect by definition. counted By definition 12 inches = 1 foot water freezes at 0 o C 1 inch = 2.54 cm

HOW MANY SIG FIGS 120 mm 6306 g L dm

HOW MANY SIG FIGS cs kg  s 360,000 mL

The Guess # ? is the furthest SIG FIG to the right 654 ft.005 s 8,500 s s

Find the Guess 120 mm 6306 g L dm

HOW MANY SIG FIGS cs kg  s 360,000 mL

The easy stuff - Sig Figs with scientific notation 2.4 x10 5 coefficient base exponent All numbers in the coefficient are significant. Ignore everything else 2.4 x Sig Figs 5 x Sig Figs x Sig Figs

Rounding to # of Sig Figs Find the left most SIG FIG. (biggest 10’s place) Count to the right the number of sig figs to keep. If the number to the right is 0-4 round “down” If the number to the right is 5- 9 round up

round to 2 SFs Round the following round to 1 SF round to 3 SFs round to 3 SF round to 2 SF round to 1 SF

Round the following round to 4 SFs round to 3 SFs round to 2 SFs round to 1 SFs round to 4 SFs round to 3 SFs round to 2 SFs round to 1 SFs