Multiple choice

A clock loses 10 minutes after every hour. If it shows the correct time at 10 A.M. on Saturday on 1st March, 2020, then when will it show the correct time as 10 again?

  1. Tuesday, 4th March, 2020

  2. Wednesday, 5th March, 2020

  3. Thursday, 6th March, 2020

  4. Saturday, 8th March, 2020

  5. Sunday, 10th March, 2020
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A Correct answer
Explanation

For a losing clock to show the correct time again, it must lose a total of 12 hours, which is 720 minutes. Since the clock loses 10 minutes every hour, it will take 720 / 10 = 72 hours (or exactly 3 days) to show the correct time again. Adding 3 days to Saturday, 10 A.M. on 1st March, 2020, brings us to Tuesday, 10 A.M. on 4th March, 2020.

AI explanation

A clock showing the correct time again must lose a multiple of 12 hours, so we first find when it loses exactly 12 hours, which equals 720 minutes. Since it loses 10 minutes every hour, we divide 720 minutes by 10 minutes per hour to get 72 hours. Adding 72 hours to 10 A.M. on Saturday brings us to exactly 10 A.M. on Tuesday, meaning the clock will show 10 again at that time. The result is Tuesday, 4th March, 2020.

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