Complete guide to Ratio and Proportion for competitive exams: basic concept of ratio (a:b), simplification of ratios, comparison of ratios, compound ratios, duplicate and triplicate ratios, sub-duplicate and sub-triplicate ratios, inverse ratio, basic concept of proportion (a:b = c:d), mean proportional, third proportional, fourth proportional, continued proportion, properties of proportion (alternendo, invertendo, componendo, dividendo, componendo-dividendo), direct proportion, inverse proportion, partnership problems (distribution of profit/loss based on capital and time), age ratio problems, mixture problems (mixing two or more ingredients), coins and currency ratio problems, distribution of amount in given ratio, and shortcut tricks for SSC, Banking, Railway, UPSC, and other government exams.