Sumit drives from home to a resort at 45 km/h. On the return trip along the same route, he averages 40 km/h and takes 1 hour longer than the outbound time. How many kilometres is each one-way trip?

Introduction / Context:
For a fixed distance D, time equals D/v. If one leg takes 1 hour more than the other, equate the difference of the two times to 1 hour to solve for D. This avoids needing the absolute times individually.

Given Data / Assumptions:

• Outbound speed = 45 km/h.
• Return speed = 40 km/h.
• Return time − Outbound time = 1 h.
• Distance each way = D (km).

Concept / Approach:
Set D/40 − D/45 = 1 ⇒ D * ( (1/40) − (1/45) ) = 1. Solve for D by taking common denominators.

Step-by-Step Solution:

Verification / Alternative check:
Outbound time = 360/45 = 8 h; return time = 360/40 = 9 h; indeed, 1 hour longer.

Why Other Options Are Wrong:
250 or 375 km give a time gap different from exactly 1 hour with the given speeds.

Common Pitfalls:
Using average speeds or adding the speeds; the key is the time difference at fixed distance.

Final Answer:
360 km