A car covers the distance from Sonagarh to Raipur in 35 min at an average speed of 69 km/h. If its average speed increases by 36 km/h for the same route, how long (in minutes) will the journey take?

Introduction / Context:This is a same-distance, different-speed time conversion. Once we compute the distance from the first scenario, we can reuse it to find the time with a higher speed. Conversions between hours and minutes must be handled carefully for accuracy.

Given Data / Assumptions:

• Initial average speed v1 = 69 km/h.
• Initial time t1 = 35 min = 35/60 h.
• New speed v2 = 69 + 36 = 105 km/h.
• Same distance each time.

Concept / Approach:Distance D = v1 * t1. New time t2 = D / v2. Convert t2 (hours) to minutes by multiplying by 60.

Step-by-Step Solution:

Verification / Alternative check:At 105 km/h, per minute distance is 1.75 km. Covering 40.25 km takes 40.25 / 1.75 = 23 minutes—consistent.

Why Other Options Are Wrong:24, 27, 29 minutes correspond to different (lower) speeds than 105 km/h for the 40.25 km route.

Common Pitfalls:Mixing hours and minutes; assuming percentage change applies to time directly (it applies inversely via speed).

Final Answer:23 min