did it take Pei more than 2 hours to walk a distance of 10 miles along a certain trial? (1mile = 1.6km)
(1) Pei walked this distance at an average rate of less than 6.4km per hour
(2) on average, it took Pei more than 9 min per km to walk this distance.
(1)은 성립된다는걸 알겠는데 (2)는 왜 성립이 되는지 잘모르겠네요.
정답은 D입니다. (2) 설명 좀 해주세요.