The method of getting the square of a number which has the last digit 5 is as follows: Add 1 to the number which is before 5 and multiply it with the same number and add 25. Example: (75)^2= 7*8=56. so the required no. is 5625.

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 I. Numbers (6 lectures) Prime numbers Interesting properties of prime numbers without proofs Ramanujan's work on the Prime Number Theorem Euclid's division algorithm Mathematical illustration through intuitive examples Visualisation through tiling analogy Encryption and Prime...

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