1. Mathematics Lesson 1 Significant Figures Lesson Objectives: To learn how to round to significant figures and how to estimate Starter Complete then negative numbers worksheet H/W Due Next Lesson! Complete the significant figures worksheet.

2. When rounding to a given number of decimal places, sometimes you round up and sometimes you round down. Why? For example 8.673 to 2dp becomes 8.67 56.78 to 1dp becomes 56.8 What is the rule? Rounding

3. When rounding the rule is: ….. 5 or more…... round up….. less than 5…… leave it as it is For example 4.67 to 1dp becomes …….. 18.923to 2dp becomes…….. What happens when your rounding to the nearest 10, 100 or 1000? What is 267 to the nearest 10? What is 346 to the nearest 100? Example

4. The Number of significant figures tells us how approximate we are allowed to be. For example 2377 to 1 significant figure is 2000 2377 to 2 significant figures is 2400 2377 to 3 significant figures is 2380 How does it work? Example

5. The number of significant figures tells us how many numbers other than zero we are allowed to have. Every thing else must be replaced with a zero. For example 5940 to 2sf becomes 5900 What is it to 1sf? Example

6. Exercise 2 Round the numbers to the given number of significant figures 1.4570 1sf 2.26511sf 3.34572sf 4.172382sf 5.9991sf 6.123962sf 7.72773sf 8.234.71sf 9.19.451sf 10.0.002351sf Exercise 1 Round the numbers to the given number of decimal places or the nearest 10, 100 or thousand 1.1.92 1dp 2.21.2572dp 3.49.4562dp 4.1.5796 3dp 5.0.2952dp 6.679 100 7.29 100 8.555 10 9.555 1000 10.8.97 10 Questions

7. Have We Met Todays Objectives? Significant Figures Lesson Objectives: To learn how to round to significant figures and how to estimate