I am confused

[ank_1]

I could solve the all the OG Difficult questions of Number properties suggested in MGMAT book within 1m 45s.But when I take a test then I fight against time and get my answers wrong. They are usually 700-800 range questions.
Why is there a difference of degree in difficulty of 700-800 questions on OG and on Practice tests? My Q scores are consistently between 46-49.Can I expect Q49 and above on my exam?

[VivianKerr]

The way I see it, private companies tests will be lower than your actual GMAT difficulty simply because they cannot adapt to your ability as quickly. If you're getting Q between 46-49 consistently, I would actually predict your true Q score might be 46 or a bit lower. If you want a 49+, I would aim to get as high a Q score as possible.

The GMATPrep will reveal all if you want to try one. I usually tell students to try to get at least 20+ pts consistently above their target score.

If your target score is 700, for example, make sure you're getting 720+ on all your practice tests. Good luck!