When Jason was heading to his office between 7 am and 8 am in the morning, he noticed that the hour hand and the minute hand of a clock formed 90 degrees. When he returned home between 5 pm and 6 pm, he noticed that the hour hand and the minute hand of the clock formed 90 degrees again. Which of the following is closest to the greatest number of hours that he was away from home?

Question

anonymous · Answer

(A) 8 hours and 20 minutes
(B) 9 hours
(C) 9 hours and 40 minutes
(D) 10 hours and 20 minutes
(E) 11 hours