A man travels a distance of 4 km every day. One day he increases his speed by 0.8 km/h than usual speed and reaches his destination 15 minutes earlier. What is the normal speed of the man?
3.2 km/h
The correct answer is 3.2 km/h.
This might be linear or, as in this case, a quadratic equation. Check the solution against the physical constraints of the problem (e.g., speed must be positive). Verify the answer by plugging it back into the original problem statement. These types of problems often require careful equation manipulation and unit conversion.
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