Understanding Significant Figures Non Zero digits are always significant. Zeroes are sometimes significant. We can use these rules to decide whether or not they are significant

Significant Figures – When are zeroes significant? Zeroes before a decimal point are significant Zeroes between Non-zero digits are significant Zeroes after non-zero digits without a decimal point or without another number after them are not significant 32000. 5 significant figures 32003 5 significant figures 32000 2 significant figures

Significant Figures – When are zeroes significant? Zeroes after decimal point are significant in the following cases When the zero is after a non-zero digits When the zero is between non-zero digits When the zeroes have no non-zero digits with them 0.000450 3 significant figures 0.04501 4 significant figures 32134.00 7 significant figures

Rounding to Significant Figures We can follow the same rules when asking to round to a certain amount of significant figures Round the following answers to 2 significant figures. 1. 23403 2. 3490 3. 0.03401 4. 0.00456 5. 239 6. 4560 = 23000 = 3500 = 0.034 = 0.0046 = 240 = 4600

Rounding to Significant Figures Round the following answers to 3 significant figures. 1. 23403 2. 34901 3. 0.03401 4. 0.004567 5. 293.01 6. 4.3061 = 23400 = 34900 = 0.0340 = 0.00457 = 293 = 4.31

Rounding to Significant Figures How many significant figures have these numbers got? 1. 23400 2. 45.30 3. 0.03401 4. 0.004567 5. 293.01 6. 4.3061 7. 300 3 4 5 1