How many times are the two hands in one straight line (overlapping or opposite) between the morning time on clock A and the afternoon time on clock B?

A shows 9:00 a.m. and B shows 2:00 p.m. The hands are in line every $\frac{360}{11}=32\frac{8}{11}$ min (0° or 180°). These instants fall at about 9:16, 9:49, 10:22, 10:54, 11:27, 12:00, 12:33, 1:05 and 1:38: 9 times. (10 counts two per hour for 5 hours.)