A clock loses 4 minutes every hour. It is set right at 6 a.m. What is the correct time when this clock shows 5:12 p.m. the same day?

4:28 p.m.Correct answerYour answer5:08 p.m.Correct answerYour answer5:56 p.m.Correct answerYour answer6:00 p.m.Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer D

Correct answer: D

For every 60 true minutes the clock shows only 56 minutes.
Time shown since 6 a.m. $= 11$ h 12 min $= 672$ minutes.
True time passed $= 672 \times \frac{60}{56} = 720$ minutes $= 12$ hours, so the correct time is 6:00 p.m.

Worth noting

5:56 p.m. adds 4 minutes for each of the 11 hours on the dial. The loss is 4 minutes per TRUE hour, and 12 true hours have passed. 4:28 p.m. subtracts instead of adding.

Concept: True time from the reading of a slow clock
Typical timeTypical: 75 s
Your timeYours: —

The rule this testsClocks that gain or lose

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Ten questions from Calendars and Clocks, at your own pace.

A clock loses 4 minutes every hour. It is set right at 6 a.m. What is the correct time when this clock shows 5:12 p.m. the same day?

Explanation