Two friends walk towards each other along a straight path 300 m long…

Step 1. Same place. $1.4t = 300 - 1.1t$, so $2.5\ \text{m/s}\,t = 300\ \text{m}$ and $t = 120\ \text{s}$.

Step 2. Where. $x_A = 1.4 \times 120 = 168\ \text{m}$.

Another way. The gap of $300\ \text{m}$ closes at $1.4\ \text{m/s} + 1.1\ \text{m/s} = 2.5\ \text{m/s}$: $\dfrac{300\ \text{m}}{2.5\ \text{m/s}} = 120\ \text{s}$.