1. **State the problem:** Two trains start 342 miles apart and travel toward each other. One train travels at 105 mph and the other at 85 mph. We need to find the time $t$ in hours when they meet.
2. **Formula and concept:** When two objects move toward each other, their relative speed is the sum of their speeds. The distance covered together equals the initial distance between them.
3. **Set up the equation:** Let $t$ be the time in hours until they meet.
The total distance covered by both trains together is $$105t + 85t = 342$$
4. **Simplify the equation:**
$$105t + 85t = 190t$$
So,
$$190t = 342$$
5. **Solve for $t$:**
$$t = \frac{342}{190}$$
Show canceling common factors:
$$t = \frac{\cancel{342}}{\cancel{190}}$$
Since 342 and 190 share a common factor 2:
$$t = \frac{171}{95}$$
6. **Final answer:**
The trains will meet after $$\boxed{\frac{171}{95}}$$ hours, which is an exact fraction with no rounding.
Train Meeting B91F3E
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