The company was still calculating the exact percentage of shares that voted, spokeswoman Kathy Shepard said.
Under terms of the buyout, Blackstone will pay Hilton shareholders $47.50 per share in cash. Including assumed debt, the total deal is valued at $26 billion (18.75 billion EUR).
Shares of Hilton Hotels rose 14 cents to $46.12 during afternoon trading. Blackstone Group shares rose 23 cents to $23.88.
The transaction must still pass regulatory approval.
Beverly Hills-based Hilton Hotels operates more than 2,800 hotels around the world. The company generated $8.11 billion (5.85 billion EUR) in revenue last year.
"As soon as we can see the concentration of American aircraft on airfields in Europe, we will simply destroy those airfields by launching our medium-range ballistic missiles at those targets"
The Russian Federal Space Agency, Roscosmos, found out the origin of the hole in the household compartment of the Soyuz MS-09 spacecraft