A bus moves at 72 km/h. What distance (in meters) does it cover in 5 seconds?

Introduction / Context:This problem combines a unit conversion (km/h to m/s) with a time-based distance calculation. It reinforces correct use of the 5/18 factor and proportional reasoning over seconds.

Given Data / Assumptions:

• Speed = 72 km/h.
• Time = 5 s.

Concept / Approach:Convert speed to m/s: v(m/s) = v(km/h) * 5/18. Then distance = speed * time in consistent units.

Step-by-Step Solution:Convert speed: 72 * (5/18) = 4 * 5 = 20 m/s.Distance in 5 s = 20 * 5 = 100 m.

Verification / Alternative check:Back-convert: 100 m in 5 s implies 20 m/s = 72 km/h, confirming consistency.

Why Other Options Are Wrong:50 m corresponds to 10 m/s (36 km/h); 60 m corresponds to 12 m/s (43.2 km/h); 74.5 m is a non-integer artifact not supported by exact conversion.

Common Pitfalls:Using 18/5 instead of 5/18 when converting from km/h to m/s; mixing seconds with hours without converting.

Final Answer:100 m