To find the distance traveled by the hour hand, subtract the beginning position from the ending position. For example, in a, the distance traveled between 4:00 and 7:00 is three hours. Since there are 12 total hours on a clock, the fraction would be 3/12 (traveled/whole revolution). Simplify further to get 1/4.
The other two problems are very similar to the explanation above. Treat the second problem's ending time as 14:00, since it is two hours after 12:00.