1. Sig. Fig. in math operations Multiplication and division: The answer to a multiplication or division problem cannot have more sig. fig. than the smallest number of sig. fig. in the problem. Example: 31.63 X 1.02 /0.0019 = 16[980.315 =17,000 (zeros are not significant)

2. Sig. Fig. in math operations Addition and subtraction: A number can have at most 1 doubtful digit (except for zeros). * indicates the doubtful digit. Adding or subtracting doubtful digits involving any digit yields a doubtful digit. Round-off the answer to 1 doubtful digit. Example: 31.63* + 0.0019* – 1.02* = 30.61*[1*9* = 30.61

3. Sig. Fig. in math operations Some numbers have an infinite number of sig. fig. Examples: 12 eggs = 1 doz 1 m = 1000 mm 1.2.080/ 5.23 = 2.2.080 X 5.230 = 3.5.23/2.0 = 4. 5.230* - 2.808* = 5. 5.23 – 2.808 = 6. 9.120 + 1.8 – 0.00037 = Solve the following problems using scientific notation. Write the answer in correct scientific notation. 7. Calculate the number of kg in 173.4 mg.