Inverse of a matrix of decimal or floating numbers. Can we find the Inverse of a 3*3 matrix having the following decimal number elements? 1.2 2.3 4.5 6.1 4.2 2.9 7.4 3.5 8.7 Thanks & Regards, Prashant S Akerkar 

$\begin{pmatrix} 2639/8482 & 426/8482 & 1223/8482 \\ 3161/8482 & 2286/8482 & 2397/8482 \\ 973/8482 & 1282/8482 & 899/8482 \end{pmatrix}$ 
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Dan 
Thanks. Can it become complex to compute the Inverse if the precision is increased for the decimal numbers in the Matrix? Example: 34.333333333 51.222222785 98.333556677 12.555555555 76.444555532 65.234567879 34.888855338 68.542666669 54.236666856 Thanks & Regards, Prashant S Akerkar 
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Dan 
If the numbers in the matrix are known to be approximate, you have a difficulty if the determinant of the matrix seems to be zero (or very close to zero). 
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$\begin{pmatrix} 34.333333333 & 51.222222222 & 98.333333333 \\ 12.555555555 & 76.444444444 & 65.222222222 \\ 21.777777778 & 25.222222222 & 33.111111111 \end{pmatrix}$ The above matrix, where the first two rows are similar to the corresponding rows in the matrix supplied by akerkarprash, but the third row is the difference of the first two rows, so that the determinant of the matrix is zero, doesn't have an inverse. Nevertheless, the website mentioned above calculates an inverse for it (as does wolframalpha). Of course the condition number is infinite in this case. If I change the final decimal place of one of the entries in this matrix, the determinant of the matrix is very small and the above website calculates its inverse inaccurately, but the condition number is large. For a matrix of this type, you are effectively asserting that its determinant can be very close to zero without its condition number being very large. Can you give an example of this? 
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