The five problems are not easy but could all be solved quickly enough by pattern discovery and application of suitable techniques. This set of solutions is rich in learning. The solutions and concepts are explained in details. Important concepts used are pattern discovery, missing element technique, similarity increase technique, graphic algebra, visualization, similar triangles, sum of inverses conversion, least value of sum of reciprocals, numerator equalization and mathematical reasoning.
The Concepts and Techniques form the BASIC SKILLSET for solving harder algebra problems EASILY IN MIND. These are the first 5 questions 1 to 5 and form the 1st part of video on the article SSC CGL Solution set 57, Algebra 13 from SureSolv.com.