Excluding operational station stops, a city bus routes at an average of 42 km/h, and including stops its net average speed is 35 km/h. For how many minutes does it stop per hour? MCQ with Answer and Explanation
Excluding operational station stops, a city bus routes at an average of 42 km/h, and including stops its net average speed is 35 km/h. For how many minutes does it stop per hour?
A. 12 minutes
B. 10 minutes
C. 14 minutes
D. 8 minutes
Answer: Option B
Solution (By JKSSB Mock Tests)
Stoppage time per hour = (42 - 35) / 42 = 7 / 42 = 1/6 hour = 10 minutes.
A car covered a distance of 200 km at a uniform speed. If the speed is reduced by 10 km/h, the time taken increases by 1 hour. Find the original speed.
Explanation:
Let original speed be s. 200 / (s - 10) - 200 / s = 1 => 200(s - s + 10) = s(s - 10) => 2000 = s(s - 10). Solving s^2 - 10s - 2000 = 0 gives (s - 50)(s + 40) = 0. Since speed is positive, s = 50 km/h.
Explanation:
Let speed of stream be s. Downstream speed = 6 + s. Upstream speed = 6 - s. Given: 2 * (6 - s) = 6 + s => 12 - 2s = 6 + s => 3s = 6 => s = 2 km/h.
No comments yet. Be the first to start the discussion!