A clock is 6 minutes slow at 2:20 PM and 12 minutes slow at 8:20 PM. At what time (in AM) will it show the correct time?
Show answer & explanation
Correct answer: A
Explanation
At 2:20 PM, the clock is 6 minutes behind.
At 8:20 PM, the clock is 12 minutes behind.
That means, in 6 hours, the clock has gained 6 minutes more.
⇒ Loss of clock = 1 minute per hour
Now, at 8:20 PM, the clock is 12 minutes behind. It needs 12 more hours to show the correct time, because every hour it gains 1 minute, and in a 12-hour cycle, it will match the correct time again.
8:20 PM + 12 hours = 8:20 AM