At 4 o'clock, the hands of the watch are 20 min.spaces apart. To be in opposite directions they must be 30 min. spaces apart :. Minute hand will have to gain 50 min. spaces. 55 min. spaces are gained in 60 min. 50 min. spaces are gained in` (60/55 xx 50)` min. or` 54 6/11` min. :. Required time` = 54 6/11` min. past 4.