1971 AMC 12 Problem 34
Attempt Problem 34 of the 1971 AMC 12 below, then check your answer against the professionally curated solution from LIVE by Po-Shen Loh. You can also try the full timed exam, view all 1971 AMC 12 solutions, or check the answer key.
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34.
An ordinary clock in a factory is running slow so that the minute hand passes the hour hand at the usual dial positions ( o’clock, etc.) but only every minutes. At time and one-half for overtime, the extra pay to which a -per-hour worker should be entitled after working a normal -hour day by that slow-running clock is:
Answer: B
Small hint:
A normal clock’s hands pass every minutes
Big hint:
Eleven slow-clock intervals total displayed hours but hours minutes of real time
Solution:
Successive hand-overlaps are real minutes apart, while this slow clock displays minutes between them. Thus displayed hours correspond to real minutes, since Eight displayed hours therefore take hours minutes, so the overtime is minutes. At per hour, that pays
Therefore, the correct answer is B.