Question

At what time between 5:30 and 6 will the hands of a clock be at right angles?
(A) 43 5 min.past5
11
(B) 43 7 min.past5
11
(C) 40min.past5 (D) 45 min past 5

Answer 1

Answer :

We know :

At 5 o'clock, the hands are 25 min. spaces apart.

To be at right angles and that too between 5 : 30 and 6 : 00 ,

The minute hand has to gain (25 + 15) = 40 min. spaces.

We know

55 min. spaces are gained in 60 min.
So ,
1 min spaces are gained in $\frac{60}{55}=\frac{12}{11}$ min.
Then
40 min. spaces are gained in $\frac{12}{11}\times 40=\frac{480}{11}=43\frac{7}{11}$ min
So,

Required time = $43\frac{7}{11}$ past 5 : 00

Option ( B ) ( Ans )