A clock is displaying correct time at 9 am on Monday. If the clock loses 12 minutes in 24 hours, then the actual time when the clock indicates 8 : 30 pm on Wednesday of the same week is = ?
A. 8 pm
B. 7 pm
C. 9 pm
D. 8 : 59 : 45 pm
Answer: Option C
Solution(By Examveda Team)
Time interval from 9 am on Monday to 8 : 30 pm on Wednesday.$$\eqalign{ & {\text{ = }}\left( {24 \times 2.5} \right) - {\text{0:30 hours }} \cr & {\text{ = 60}} - {\text{0}}{\text{:30 hours}} \cr & {\text{ = 59 hours 30 minutes}} \cr & = 59\frac{{30}}{{60}} \cr & = 59\frac{1}{2} \cr & = \frac{{119}}{2}{\text{ hours}} \cr & {\text{Also 24 hours}} - {\text{12 minutes}} \cr & = {\text{23 hours 48 minutes}} \cr & = 23 + \frac{{48}}{{60}} \cr & = 23\frac{4}{5} \cr & = \frac{{119}}{5}{\text{ hours}} \cr & \therefore \frac{{119}}{2}{\text{ hours of this clock}} \cr & = \frac{{24 \times 5}}{{119}} \times \frac{{119}}{2} \cr & = 60{\text{ hours}} \cr & \left( {60 - \frac{{119}}{2}} \right){\text{ hours}} \cr & {\text{ = }}\frac{{120 - 119}}{2}{\text{ hours}} \cr & {\text{ = }}\frac{1}{2}{\text{ hours}} \cr & = 30{\text{ minutes}} \cr} $$
Hence, the correct time is 30 minutes after 8:30 pm i.e., 9 pm
Related Questions on Clock
The reflex angle between the hands of a clock at 10.25 is:
A. 180º
B. $${\text{192}}{\frac{1}{2}^ \circ }$$
C. 195º
D. $${\text{197}}{\frac{1}{2}^ \circ }$$
A clock is started at noon. By 10 minutes past 5, the hour hand has turned through:
A. 145º
B. 150º
C. 155º
D. 160º
A. $$59\frac{7}{{12}}$$ min. past 3
B. 4 p.m.
C. $$58\frac{7}{{11}}$$ min. past 3
D. $$2\frac{3}{{11}}$$ min. past 4
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