Offeror says, "I'll sell you my car for $10,000." Offeree says, "I accept your offer, but I will pay only $9,700." As a result, at this point:

There are two open offers.

This was a conditional acceptance.

Offeror must sell their car to the Offeree if Offeree gives Offeror $10,000.

The only open offer is for $9,700.