Correct option is (d) 8, 64
Let the smaller number be x.
Hence
\(\frac{192}x - \frac{192}{x^2} = 21\)
192x − 192 = 21x2
21x2 − 192x + 192 = 0
7x2 − 64x + 64 = 0
(x − 8)(7x − 8) = 0
Hence the number has to be a integer.
Therefore
x = 8
Hence its square is 82 = 64.