Find at what time be tween 8 and 9 O'clock will the ha nds of a clock be in the same straight line but not together.

Options

A. a. `10(10)/(11)` min past 8
B. b. `50(10)/(11)` min past 8
C. c. `10(12)/(11)` min past 8
D. d. 10 min past 8

Answer

A

Explanation

Fig (i) shows the positions of the hands of the clock and it is clear that they are 20 min apart. To be in the straight line, they have to be 30 min apart So, the minute hand will have to move 10 min space in order to be 30 mm apart from hour hand. 55 min are gained in 60 min. 10 min. will be gained in
`(60)/(55) xx 10 = (12)/(11) xx 10` min
Therefore, the hands will be at right angle but not together at `10(10)/(11)` min past 8.