2. Three Significant Figures Three significant figures. If you approximate a number, what are the most significant 3 numbers that you can give. E.g. 0.74341 88572 Geogebra (We’ll revise this at the end)

3. Points you’ve discovered: 1. Zeros at the start of the number do not count as significant figures. (E.g. 0.00231) 2. 3. 4. Three Significant Figures

4. Rounding Decimals to 3 s.f 0. 8 2 3 4 5 5 or bigger ? 0.823 3.9 7 6 5 or bigger ? 3.98 1 5. 3 6 1 5 or bigger ? 15.4 1 8. 0 3 5 or bigger ? 18.0 0. 9 2 0 8 5 or bigger ? 0.921 1 8. 0 5 5 or bigger ? 18.1 No Yes

5. Rounding Decimals and Whole Numbers to 3 s.f 0. 3 9 9 8 5 or bigger ? 0.400 1 7. 9 9 5 or bigger ? 18.0 4 2 3. 1 1 5 or bigger ? 423 Yes No 4 8 8 7 5 or bigger ? 4890 7 2 5 1 0 5 or bigger ? 72500 8 9 9 9 9 9 5 or bigger ? 900000 Yes No Yes

6. Write these numbers to 3 significant figures: 1.3.2441 2.5.03698 3.0.84677 4.0.071233 5.19.03 6.0.29999 7.16.95 8.43227 9.1579800 10.143.2 11.196.5