GMAT Verbal Section | Official Guide 2017 Directory [verbal]

Hi..
The GMAT OG 2017 cover says there are over 900 questions..

But I see that there are 807 practice questions in OG..
If I include diagnostic 100 questions, then the total number of questions is 907..

But, somehow, I feel cheated by OG for not stating explicitly the number of only practice questions .. Anyone with same thoughts?

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