Significant Figures 1 2 3 4 Rules All

Significant Figures

1. 2. 3. 4. Rules All nonzeroes are significant Zeroes in-between are significant Zeroes to the left are not significant Zeroes to the right are not significant unless they follow a decimal. 5. All numbers in scientific notation are significant 6. Exact numbers are obtained by counting or definitions such as 1 in = 2. 54 cm, and are considered infinite in significance

Adding and Subtracting Always use the least significant decimal place. example: 1253. 747 or 1253. 757 + 1. 1 1254. 8 = 1254. 9 round up . 0365578 -. 00223 =. 03433 or 3. 433 X 10 -2

Multiplying and Dividing All ways go by the least number of significant figures. examples: 1253. 747 X 1. 1 = 1379. 1217 No only 2 sig figs, so 1400 or 1. 4 x 103 120. 0 ÷ 2. 336589 =51. 3569 but this is rounded to 4 sig figs so 51. 36

Combining the math 55. 657 -55. 654 X. 033. 000021806167 = 4. 54 following the order of operations 55. 657 - 55. 654 =. 003 which is reduced to 1 sig fig Then when finish the problem using multipling and dividing we must then use the 1 sif fig rule So our answer is . 00002 or 2 x 10 -5

Give it a try • 45. 6632 -45. 6619 x 100 =. 002846931446 45. 6632 – 45. 6619 =. 0013 which has 2 sig figs. so. 0028

Logs • what is the log of 111. 1 = 2. 0457 • antilog of 123. 2 = =10123. 2 =1. 58489 x 10123 =2 x 10123

Which are Exact Numbers? • • • 1 dozen eggs 25 students 1000 mm = 1 m 1 km = 0. 621 mi 2. 54 cm = 1 in 6. 02213 x 1023