A train covers a distance of 360 km at a uniform speed. If the speed had been 5 km/h more, it would have taken 1 hour less. What was the original speed?
A35 km/h
B40 km/h
C45 km/h
D50 km/h
Explanation
Let speed be v. 360/v – 360/(v+5) = 1 => 360[5 / (v(v+5))] = 1 => v(v+5) = 1800 => v^2 + 5v – 1800 = 0 => (v + 45)(v – 40) = 0 => v = 40 km/h.
Exam Relevance
- Topic: Speed, Time & Distance
- Subtopic: Speed Variations
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