At what time between 4 and 5 oclock will the hands of a watch point in opposite directions?
45 min. past 4
40 min. past 4
50$ \dfrac{4}{11} $min. past 4
54$ \dfrac{6}{11} $min. past 4
Explanation:
At 4 oclock, the hands of the watch are 20 min. spaces apart.
To be in opposite directions, they must be 30 min. spaces apart.
$\therefore$ Minute hand will have to gain 50 min. spaces.
55 min. spaces are gained in 60 min.
50 min. spaces are gained in$ \left(\dfrac{60}{55} \times 50\right)$min. or 54$ \dfrac{6}{11} $min.