Slow Clock - Mathlete's Corner

Slow Clock Problem: The clock shown in the figure below loses twelve minutes every hour. It shows the correct time now. In how many hours will it next show the correct time? This is a classic ratio and proportion problem. Let's look at the following pictures. The green clock has the correct time. The blue one is the slow clock. After 1 hour: After 5 hours: After 10 hours: Basically, since it loses 12 mins every hour,  it takes 60/12 = 5 hours to lose 60 mins or 1 hour. So every 5 hours the slow clock loses 1 hour. Since it is always behind the real clock,

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