When I went to receive the gold medal I won in the OBMEP, the following information appeared on the passenger cabin screens of my flight to Recife:

$$
\begin{aligned}
\text { Average speed: } & 864 \mathrm{~km} / \mathrm{h} \\
\text { Distance from the departure location: } & 1222 \mathrm{~km} \\
\text { Arrival time in Recife: } & 1 \mathrm{~h} 20 \mathrm{~min}
\end{aligned}
$$

If the plane maintained the same speed, then what is the distance, approximately, in kilometers, between Recife and the city where my flight started?
(a) 2300
(b) 2400
(c) 2500
(d) 2600
(e) 2700
The correct option is (b).

At the moment the information was given, the remaining flight time was $1 \mathrm{~h} 20 \mathrm{~min}$, or $4 / 3$ of an hour. Therefore, at that moment, the distance to Recife was $864 \times \frac{4}{3}=1152$ $\mathrm{km}$. Since we were $1222 \mathrm{~km}$ from the departure city, the distance between this city and Recife must be $1152+1222=2374 \mathrm{~km}$. Among the given options, the closest one is $2400 \mathrm{~km}$.