1. 1 Press Ctrl-A ©G Dear 2010 – Not to be sold/Free to use Fixed Interest Stage 6 - Year 11 Mathematics

2. 2 Operations with Percentages One number as a percentage of another: Example 1: Find 30g as a percentage of 200g. 30 200 x 100%= 1.5%

3. 3 Operations with Percentages Exercises Beat The Clock Start 5 seconds of 1 minute as a percentage. 109876543210 8.3% Start 108 kg of 1.2 tonne as a percentage. 109876543210 9% Start 500 m 2 of 1.2 ha as a percentage. 109876543210 4.16%

4. 4 Increasing and Decreasing: Example 2: Increase 30g by 12%. 100% + 12% =112% =1.12 Increase = 1.12 x 30 = 33.6g Example 3: Decrease 320m by 8%. 100% - 8% =92% =0.92 Decrease = 0.92 x 320 =294.4m Operations with Percentages

5. 5 Operations with Percentages Exercises Beat The Clock Start Increase 30 minutes by 20% 109876543210 36 minutes Start Decrease 1.2 tonne by 5%. 109876543210 1.14 tonne Start Increase $120 by 10% and then Decrease the answer by 10% 109876543210 $118.80