A driver is traveling at 60 km/h. Is the driver speeding if the speed limit is 45 mph?
A) Yes
B) No
The correct answer and explanation is :
Correct Answer: A) Yes
To determine whether the driver is speeding, we need to compare their current speed of 60 kilometers per hour (km/h) to the speed limit of 45 miles per hour (mph). Since the two units are different, we must first convert one to the other for an accurate comparison.
Step 1: Conversion from km/h to mph
The standard conversion factor between kilometers and miles is:
1 mile ≈ 1.609 kilometers
To convert 60 km/h to miles per hour (mph), divide 60 by 1.609:
[
\frac{60\ \text{km/h}}{1.609} \approx 37.28\ \text{mph}
]
Step 2: Compare with the speed limit
Now that we’ve converted the driver’s speed to approximately 37.28 mph, we can compare it to the posted speed limit of 45 mph.
[
\text{Driver’s speed: } 37.28\ \text{mph} \
\text{Speed limit: } 45\ \text{mph}
]
Since 37.28 mph is less than 45 mph, it appears at first that the driver is not speeding.
However, that contradicts our answer. Let’s double-check by doing the reverse—convert the speed limit from mph to km/h.
Step 3: Conversion from mph to km/h
1 mile ≈ 1.609 kilometers
So:
[
45\ \text{mph} \times 1.609 \approx 72.41\ \text{km/h}
]
Now compare:
- Driver’s speed: 60 km/h
- Speed limit in km/h: ≈ 72.41 km/h
Clearly, 60 km/h < 72.41 km/h, so the driver is below the speed limit.
Correction
After verifying both conversions, we conclude:
- 60 km/h is approximately 37.28 mph
- The speed limit is 45 mph (≈ 72.41 km/h)
Therefore, the driver is NOT speeding.
Corrected Answer: B) No
Apologies for the initial mislabeling. The driver is traveling below the posted speed limit. This demonstrates the importance of accurate unit conversions in real-world scenarios such as interpreting speed limits when traveling internationally.