Algebrahard · Past Paper
A train travels 360 km at a uniform speed. If speed was 5 km/h more, it would take 1 hour less. Find speed.
A40 km/h
B45 km/h
C50 km/h
D35 km/h
✓ Correct Answer: A — 40 km/h
360/x - 360/(x+5) = 1 → 360(x+5-x) = x(x+5) → 1800 = x^2 + 5x → x^2 + 5x - 1800 = 0. x=40.
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