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🧮 Free course

Aptitude & Reasoning

Do the arithmetic in your head, fast, while someone is watching.

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What you will learn

  1. Percentages, and the base you forgot
    Every percentage trick question works the same way: it changes the base halfway through the sentence and hopes you don't notice.
  2. Ratios, proportion and mixtures
    A ratio never tells you how much — it tells you how many parts, and every ratio question is solved the moment you find what one part is worth.
  3. Time, speed and distance
    Drive to Mysuru at 60 km/h and back at 40, and your average is 48, not 50 — because you spent longer at the slow speed, and time, not distance, is what averages are weighted by.
  4. Work, rate and pipes
    A fills the tank in 4 hours and B in 6 — together it is not 5 hours and not 10, it is 2.4, because you add speeds of work, never the days.
  5. Averages and weighted averages
    A batsman averaging 40 after 10 innings needs 95 in the next one to reach 45 — because an average is a total in disguise, and every innings has to be lifted by 5.
  6. Profit, loss and discount chains
    "50% off + extra 20% off" is not 70% off, and every profit-and-loss question in a placement test is built on someone believing it is.
  7. Permutations, combinations, probability
    Pick two players from fifteen and you get 105 pairs; name a captain and a vice-captain and the same fifteen give 210 — one question, does order matter, decides half the marks in this topic.
  8. Number series and pattern spotting
    Every number series in a placement test comes from a list of about eight rules — check them in the right order and most series fall in under twenty seconds.
  9. Data interpretation: tables and charts under time
    A DI set gives you five questions and eight minutes; the toppers finish early because they compute only what the options force them to.
  10. Estimation: order-of-magnitude answers
    "How many events per second?" is not a trick question. It is a test of whether you can be roughly right in thirty seconds instead of precisely stuck.

How the course works