1. MATH WITH SIG FIGS SIG FIGS HELP YOU ROUND OFF ANSWERS WITH CORRECT PRECISION. AN ANSWER CAN ONLY BE AS PRECISE AS YOUR LEAST PRECISE MEASUREMENT

2. RULES FOR ROUNDING WITH SIG FIGS MULTIPLICATION / DIVISION – ROUND THE FINAL ANSWER OFF TO THE MEASUREMENT WITH THE LEAST NUMBER OF TOTAL SIG FIGS. –EX: (4.56 cm)(72.12 cm)(54 cm)= CALCULATOR ANSWER: 17758.8288 cm 3 ROUNDED ANSWER: 18000 cm 3

3. –A–ADDITION/SUBTRACTION ROUND THE FINAL ANSWER TO THE MEASUREMENT WITH THE LEAST NUMBER OF DIGITS AFTER THE DECIMAL. EX: 6.78 cm + 23.5 cm + 0.865 cm= –C–CALCULATOR ANSWER: 31.145 cm –R–ROUNDED ANSWER: 31.1 cm

4. PRACTICE PROBLEMS COPY AND WORK IN NOTEBOOK 1) (6.54m)(7.9m)(2.456s) = 2) 9.560g / 66.0mL = 3) 5.78g + 4.9g + 389.0mg = 4) 8.45L – 0.65L=

5. ANSWERS 1) (6.54m)(7.9m)(2.456s) = –C–CALC. ANS: 126.891696 m 2 *s –R–ROUNDED ANS: 130 m 2 *s 2) 9.560g / 66.0mL = –C–CALC. ANS: 0.14484848 g/mL –R–ROUNDED ANS: 0.145 g/mL

6. 3) 5.78g + 4.9g + 389.0mg = 5.78g + 4.9g + 0.3890g = –CALC. ANS: 11.069 g –ROUNDED ANS: 11.1 g OR CHANGE TO g

7. 3) 5.78g + 4.9g + 389.0mg = CHANGE TO mg 5780 mg + 4900 mg + 389.0 mg= –CALC. ANS.: 11069 mg –ROUNDED ANS.: 11100 mg

8. 4) 8.45L – 0.65L= –CALC. ANS: 7.8L –ROUNDED ANS: 7.80L