Final answer:
To convert 55.0 mph to km/h, multiply by the conversion factor of 1.609 km/mi, resulting in 88.495 km/h, which is approximately 88.5 km/h (option c is the correct answer).
Step-by-step explanation:
To convert a speed from miles per hour (mph) to kilometers per hour (km/h), you can use the conversion factor that 1 mile is approximately equivalent to 1.609 kilometers (km). Therefore, to convert 55.0 mph to km/h, you multiply by this conversion factor:
Speed in km/h = Speed in mph × Conversion factor
Speed in km/h = 55.0 mph × 1.609 km/mi
Speed in km/h = 88.495 km/h
When rounded to one decimal place, the speed is 88.5 km/h, which corresponds to answer choice (c).
The correct conversion of the speed from 55.0 mph to km/hr is approximately 88.6 km/hr, making option (c) the accurate choice. This conversion is crucial for international travel or understanding speed in regions that use the metric system.