At what time, in minutes, between 5 and 6'o clock will the hands of the clock be at right angles for the first time?
A
10(10/11)
B
11(5/11)
C
5(5/11)
D
9(7/11)
Correct Option - A
Explaination
At 5'o clock, the hour hand is 25 minute spaces ahead of the minute hand.
To be at right angles, they should be 15 minute spaces apart.
The minute hand has to gain 10 minute spaces over the hour hand.
55 minute spaces are gained in 60 minutes.
10 minute spaces are gained in
(60/55)*10 = 120/11
= 10(10/11) minutes