Resources available for improving quantitative aptitude for the UPSC exam include specialized preparation books, online courses, and practice question banks. Popular titles such as “Quantitative Aptitude for Competitive Examinations” often provide comprehensive coverage of necessary topics. Additionally, websites and apps offering mock tests and timed quizzes can help candidates measure their progress and identify weak areas. Engaging with forums or study groups can offer further insights and peer support. Consistent practice and review of mathematical concepts, combined with solving previous year's questions, ensure that aspirants build the necessary skills to excel.