This problem involves calculating the time it takes for two runners, moving in opposite directions on a circular track, to meet for the first time. We can solve this using the concept of relative speed.
When two objects move in opposite directions, their relative speed is the sum of their individual speeds. This is the speed at which the distance between them decreases.
Relative Speed ($v_{rel}$) = $v_A + v_B$
In this case, $v_{rel} = 6 \text{ m/s} + 4 \text{ m/s} = 10 \text{ m/s}$.
For the runners to meet for the first time, the total distance covered by both combined must equal the length of the circular track.
Time = Total Distance / Relative Speed
Time = $\frac{\text{Track Length}}{v_{rel}}$
Time = $\frac{400 \text{ meters}}{10 \text{ m/s}}$
Time = 40 seconds
The runners will meet for the first time after 40 seconds.
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