A clock gets slower by 5 seconds in every 2 hours. If the correct time is set on the clock at 7 A.M. on Sunday 26th, January, what will be the exact time on the clock at 5 P.M. on Monday, 27th January in hrs, minutes and seconds?
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → 4:58:35 P.M.
The clock loses time at a steady rate, so the time it loses grows in proportion to the time passed. It was set right at 7 A.M. on Sunday, so it starts with no error, and at 5 P.M. on Monday it is behind by the whole loss of that period.
Time passed: 7 A.M. Sunday to 7 A.M. Monday is 24 hours, and 7 A.M. to 5 P.M. on Monday is 10 hours more, so 34 hours in all
The clock loses 5 seconds in every 2 hours, that is 2.5 seconds an hour
Loss in 34 hours \(=34\times2.5=85\) seconds \(=\) 1 minute 25 seconds
The clock shows 5:00:00 P.M. − 1 min 25 s \(=\) 4:58:35 P.M.