$\text{A}$ and $\text{B}$ are two railway stations $90 \; \text{km}$ apart. A train leaves $\text{A}$ at $9:00 \; \text{am},$ heading towards $\text{B}$ at a speed of $40 \; \text{km/hr}.$ Another train leaves $\text{B}$ at $10:30 \; \text{am},$ heading towards $\text{A}$ at a speed of $20 \; \text{km/hr}.$ The trains meet each other at
- $ 11:45 \; \text{am} $
- $ 10:45 \; \text{am} $
- $ 11:20 \; \text{am} $
- $ 11:00 \; \text{am} $