At the rate of 20 miles per hour, the car will travel 20 miles every 60 minutes, or a third of a mile every minute. This means that it will travel a mile in 3 minutes. For the car travelling at 30 miles per hour, it will travel half a mile every minute, or a mile every 2 minutes. 3-2=1 minute, or choice A. Hope this helps!
The 33rd percentile corresponds to a score of 542.4. In order for a score to be within the top 67%, it must be above that value. The least integer above that value is 543.
