Since, 99 is the largest 2 digit no. and after doing the process of finding the square root , the remainder 18 is left with 9 as quotient.

Therefore,

99-18 = 81

And we know that 9?9 i.e. square of 9 is 81.

Therefore the largest 2 digit no. which is a perfect square too is 81.

Therefore,

99-18 = 81

And we know that 9?9 i.e. square of 9 is 81.

Therefore the largest 2 digit no. which is a perfect square too is 81.

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