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This problem trains for: SAT-I, GMAT, AMC-8, CAHSEE, Math Kangaroo 5-6.

A cesium-beam atomic clock measures frequency with an accuracy of 2 nanoseconds per day. How many years does it take for such a clock to become off by a whole second? The average number of days per year is 365.2425.

We need to convert nanoseconds per day to seconds per year.

Find how many years are equivalent to 108 days.

Due to leap years, the average number of days per year is:

It takes approximately 1,400,000 years for this clock to become off by a whole second.