get a9 in gcse mathematics numbers ratios percentages

1. Introduction 0:00 Introduction 2. Arithmetic, Multiples and Factors 0:31 Calculations 6:40 Multiples and Factors 10:58 Prime Numbers and Prime Factors 13:45 Lowest Common Multiple (LCM) and Highest Common Factor (HCF) 3. Approximations 18:07 Rounding 24:02 Upper and Lower Bounds 4. Fractions 29:00 Equivalent Fractions 38:50 Mixed Numbers 42:06 Ordering Fractions 44:02 Adding and Subtracting Fractions 45:52 Multiplying and Dividing Fractions 49:50 Fractions and Decimals 54:53 Fractions Problems 5. Ratios and Proportions 1:02:46 Ratios 1:05:12 Dividing in a Given Ratio 1:11:09 More Ratio Problems 1:13:44 Proportion 1:15:42 Ratio and Proportion Problems 6. Percentages 1:22:12 Percentages 1:26:16 Percentages, Fractions and Decimals 1:35:11 Percentage Increase and Decrease 1:37:07 Compound Percentage Change 1:44:22 Percentages Problems