I have a 2011 Toyota Prius, and where I live there are only two types of gasoline: 90 and 95 (RON).
In the refueling section in the car manual it says: "Use unleaded gasoline. (Octane Rating 87 [Research Octane Number 91] or higher)"
Does 90 RON correspond to a rating lower than 87?
Can I use the 90 RON gas? What are the consequences if I do so?