Hi deepakdevi,
A practice CAT score result is only as realistic as you make the CAT-taking 'process.' If, when you took this CAT, you made sure that it 'lined up' with all of the aspects of what you'll face on the Official GMAT, then this Score is likely accurate. To be more specific, you would need to take the ENTIRE CAT (including the Essay and IR sections), at the same time of day as your Official GMAT, away from home, under test-like conditions, etc. The more that your CATs deviate from what you'll face on Test Day, the more likely your score results are to be 'off.'
1) When are you planning to take the GMAT?
2) What is your score goal?
GMAT assassins aren't born, they're made,
Rich